Theater Ballistic Missile Defense from the Sea
Charles C. Swicker - Newport Paper 14


Naval Theater Ballistic Missile Defense Overview

AS THE NEW MILLENNIUM APPROACHES, the United States looks out on a world in ferment—nations and peoples attempting to define their place in an international order shattered by the end of nearly three generations under a bipolar system. Pessimists preach a dark future: "Technology is changing how man knows, and the resulting dislocations are culturally cataclysmic. Half the world is looking for God anew, and the other half is behaving as if no god exists."4 Optimists couch their views in terms reflecting the dichotomy within the common Chinese character for chaos and opportunity. "We live at a fantastic moment of human history. . . . The spread of the Third Wave economy has galvanized all of the Asia Pacific region, introducing trade and strategic tensions, but at the same time opening the possibility of rapidly raising a billion human beings out of the pit of poverty."5

The Joint Chiefs of Staff take the middle ground and see "a world in which threats are widespread and uncertain, and where conflict is probable, but too often unpredictable."6 To the JCS, that world holds four principal dangers for the United States:

Threat, Vulnerability, and Defense

These four challenges are intertwined in a dynamic that is emerging from the confluence of international instability and the worldwide diffusion of technology. As more and more nations consider themselves to be standing alone before their enemies, no longer sheltered by the suzerainty of a superpower, they also are increasingly able to buy, steal, or indigenously develop the technologies through which they hope to "achieve strategic security—the chance of a millennium."8 Often, these striving nations believe that this chance is to be found in the complementary technologies and synergistic power of theater ballistic missiles and the second "principal danger"—weapons of mass destruction.

TBM and WMD Proliferation. Evolution, whether of organisms or organizations, arises from the selective pressure exerted by the surrounding environment and will continue for the duration of that pressure. The selective pressure of the international environment may drive the leaders of developing nations to acquire theater ballistic missiles as a means to achieve strategic security, both for their people and for themselves. This is the vital, indeed primal, "demand side" of the proliferation equation. Why nations who otherwise lack significant political or military leverage wish to acquire such disproportionate capabilities is often more important than how they achieve that goal. In a world of increasingly decentralized technology and an ever-expanding base of scientific knowledge, these nations will succeed. Unless the pressure for nations to assure their own strategic security can be eliminated, supply-side controls on proliferation are doomed to eventual failure. Determined proliferators will arm themselves before they will feed their people. For example:

The Iraqi government has used a covert network of purchasing agents and dummy companies to buy millions of dollars worth of sensitive missile parts from firms in Europe and Russia. . . . The missile-related orders reflect Iraq's willingness to spend tens of millions of dollars to rebuild a key facet of its prewar military capability, even though the country's leaders claim it is financially strapped.9

Consider what Third-World nations stand to gain from such decisions. These weapons confer national prestige upon a regime and its leader; they allow formidable international intimidation of regional foes; and they are available on the world arms market as turnkey systems with required training levels that are achievable in the developing world.

No longer the exclusive Cold War preserve of Nato and the Warsaw Pact, TBMs have been successfully employed in tribal civil wars in Afghanistan and Yemen, proving that neither a national technical infrastructure nor a highly trained tactical air arm is necessary to strike quickly and deeply at an enemy's key military and political targets.10 Even against a nation with modern, well-trained forces, unless capable theater ballistic missile defenses are fielded, such strikes will get through, expending replaceable TBM "ammunition" rather than valuable TACAIR pilots.11

By 2008, more than twenty countries will be able to field some form of TBM capability, including key regional powers in the flashpoints of northeast Asia, the South China Sea littoral, the Indian subcontinent, southwest Asia, the Levant, and North Africa. International efforts to counter TBM proliferation, including such Western supply-side "technology cartels" as the missile technology control regime (MTCR), may increasingly push these same nations toward the development of indigenous technology.

The nature of indigenous technology in the Third World will tend to limit missile accuracy more than it will warhead lethality. In this regard, the intelligence community will have to closely monitor emergent TBM applications of global positioning system (GPS) technology. In general, however, the precise guidance systems necessary to achieve a small circular error probable (CEP) with a ballistic system are, simply, more difficult to design and manufacture than are, for example, basic chemical warheads for that same system. This "selective pressure" will thus encourage the evolution of systems with poor accuracy but powerful payloads.

Historically, the targets of choice for systems thus constrained have been civilian population centers—large, soft, stationary targets of dubious military value but of great political importance. Therefore, these systems may not be able to defeat a developed nation militarily, but they can confer potent political leverage through the threat, as French strategic planners once put it, of "tearing off an arm."

Readiness to exercise that option, though, may not be constrained by traditional concepts of strategic deterrence. Speaking specifically of small nuclear forces in the developing world, Jerome Kahan identifies three factors which increase the likelihood of use for any form of WMD:

Strategic discourse between . . . adversaries may be nonexistent, raising the prospect of a breakdown in deterrence at the regional level. . . .

Third World states tend to have imperfect and incomplete intelligence information about their relative positions in a conflict. . . .

Small nuclear forces, especially in the hands of technically unsophisticated countries, may well be deficient in command and control arrangements.12

Thus, by 2008, the United States may face a variety of regional powers deploying tenuously controlled TBM systems of prodigious reach with problematic accuracy offset by powerful warheads.

Why, in a discussion of theater ballistic missile defense, should weapons of mass destruction, especially nuclear WMD, be emphasized when these devices have yet to be combined with TBMs and used in regional conflict? The "leverage" inherent in a given weapon system derives, in part, from how effectively it can engage and neutralize its intended target. During Operation Desert Storm, the United States gained great leverage from the conventionally armed Tomahawk land attack missile (TLAM), successfully conducting operational fires with this weapon, to the full depth of the theater, in the critical early days of the war. That leverage was gained by what was, in effect, nothing more than a slow-flying 1,000-lb. bomb. However, TLAM was in reality a "system of systems," a weapon whose nominal power was multiplied by precise accuracy gained from complex guidance systems, systems in turn supported by an unrivalled National Technical Intelligence system, a comprehensive Mapping, Charting and Geodesy system, and a mission-planning system employing a national network of experts with access to massive computational power. All the missile had to do was fly to a given point in three dimensions and explode—but the synergistic support systems that planned the mission for that one missile had marked and mensurated that point to within inches.

In developing nations, these support systems are generally missing. National technical intelligence with which to conduct strategic reconnaissance is limited or nonexistent (as noted by Kahan). In a permissive prehostilities environment, an intelligence operative with a hand-held GPS can record the coordinates of a stationary target, but the TBM system tasked against that target is unlikely to be able to take advantage of the precision thus provided. Though enhanced ballistic missile systems that approach U.S. cruise missile accuracy will someday be fielded, supply-side proliferation controls and the resultant limitations of indigenous technology will tend to push that day into the future. Thus, while First World land attack cruise missiles gain their leverage through stealth and accuracy derived from a system of systems, Third World theater ballistic missiles stand alone and must rely on speed and brute force.

The solution for poor targeting of denied areas and poor system accuracy once a TBM gets there is to increase warhead lethality. As long as accuracy remains constrained, this is an evolutionary imperative for TBM systems and therefore represents an imminent threat for TBMD forces. In 1991, crude chemical warheads were available for Iraqi Scuds, but were not used. In 2008, TBM-weaponized WMD could include bulk chemical and biologic warheads, chemical submunitions, and that most challenging threat of all—the TBM-carried nuclear weapon.

Much debate currently swirls about the defensive difficulties posed by various incarnations of putative chemical submunition warheads. The sound and fury of these cost and operational effectiveness analysis (COEA) arguments tend to push the reality of the nuclear threat into an indeterminate future scenario. Modern chemical weapons are indeed deadly, and it is possible to design a worst-case submunition warhead to carry them, which will give TBMD interceptor engineers cold sweats—but an important fact gets lost in the debate. Chemicals and bioagents kill. Nuclear weapons obliterate.

Since August 1945, nuclear weapons have had a special resonance in world affairs, unmatched by the other two members of the WMD unholy trinity. The use of chemical weapons in recent conflicts has been universally decried—and, in those cases, universally tolerated. One wonders what the world community would have done if the final offensives of the Iran-Iraq war had been heralded by tactical nuclear exchanges rather than by the muffled midnight bursts of mustard and cyanide shells. Likewise, had the Libyan CW plant at Rabta actually been producing highly enriched uranium (HEU), might it not have disappeared under a swarm of TLAM long before the hardened facility at Tarhuna was built? Also, note that the Ballistic Missile Defense Organization (BMDO) draft Theater Missile Defense Command and Control Plan contains a nuclear—not a biological, not a chemical—annex, for nuclear weapons attack everything simultaneously, burning, blasting, poisoning, and causing the C2-vital electromagnetic spectrum to fibrillate even as they turn the very sand to ash and glass.

Proliferators in the developing world know this. Chemical and biological weapons are more easily produced—but they are the B-Team. A-Team capability is available for a sufficient investment of time and treasure. Israel, India, Pakistan, South Africa, and North Korea know this. It is hoped that before the murder of Hussein Kamel al-Majid in March 1996, the intelligence community interrogated the Iraqi inner-circle defector and WMD-development chief concerning the details of the Iraqi nuclear program in early 1991—thereby suggesting how the similar Iranian program may be progressing today. "The Iranian effort to acquire nuclear weapons technology mirrors the push by President Saddam Hussein to build a nuclear bomb in Iraq over the last 15 years. The Iranians use many of the old Iraqi smuggling routes and contacts. . . ."13 Both in the Gulf and beyond, the TBM-WMD threat is imminent. By expedience and necessity, that threat in the short term will be chemical and biological. By evolutionary imperative, the threat in the future will be nuclear.

Three Centers of Gravity. WMD capability will give theater ballistic missiles a degree of leverage they have not heretofore demonstrated. Conventional Scuds arcing into Haifa and Tel Aviv presented the United States with a severe, but ultimately manageable, operational and diplomatic challenge. The same could not have been said if the Scuds had been carrying weapons of mass destruction. WMD-capable TBMs will be able to hold at risk not only specific individual targets, but entire centers of gravity, both military and political.

At the operational-tactical level of conflict, an enemy so equipped can threaten the military center of gravity consisting of the opposing power projection force itself. One way of doing this would be to interdict ports, airfields, supply depots, and fixed assembly areas.14 Aggressor forces employed chemical TBM barrages against just this target set early in the northeast Asia MRC of Global Wargame '95.15 Using conventional TBMs, the Iraqi military attempted the same tactic, for the same reasons, against rear areas such as Jubayl, Saudi Arabia, in 1991.16 These conventional attacks were largely ineffective. However, were a credible chemical, biological, or nuclear threat posed, it probably would force the assembly, concentration, and resupply of a power projection force to take place outside the range of hostile TBM systems; such a threat-induced operational requirement would make the movement-to-contact phase of a major campaign significantly more complex and costly.

Also at the operational-tactical level of conflict, a second way of attacking the military center of gravity is to use the TBM-WMD system against concentrated formations of combat forces. Hence, the DESERT STORM model of massive force marshaled, magnified, then suddenly unleashed in high tempo, synchronized combat probably will be difficult to emulate. Heavy ground forces concentrating in fixed assembly areas in theater would likely be superseded by more maneuverable (thus more survivable, albeit lighter) forces deployed from longer range—perhaps by means of an extended period of air and naval strike tasking, followed by airborne and amphibious operations that would themselves attempt to minimize their suitability as targets for WMD.

At the operational level of war, the WMD-TBM vulnerable center of gravity is political: the cohesion of U.S.-allied regional coalitions. Multinational operations are an integral part of the national military strategy, for "our Armed Forces will most often fight in concert with regional allies and friends, as coalitions can decisively increase combat power and lead to a more favorable outcome to a conflict."17 However, when facing a TBM-armed adversary during the time frame of this study, the territory of the United States itself is unlikely to be directly threatened, while that of regional allies may well be. If that threat is chemical, biological, or nuclear, the political leadership of likely coalition partners may look to their own strategic security and decide that making common cause with the United States against a local hegemon is not an attractive option. "A window for internationally supported military action against a proliferator may close as the country gains the capability to retaliate against additional countries at greater ranges."18

If, however, the National Command Authorities see U.S. vital interests set sufficiently at risk, the nation can pursue unilateral military action. This is a fundamental tenet of the national military strategy. However, such a course not only risks potential collateral damage to, and direct retaliation against, U.S. friends in the region, but also focuses attention on a vital and vulnerable third center of gravity at the strategic level of war: the political will of the American people.

Since facing German mustard gas and phosgene in 1918, American forces have not had to operate on a WMD battlefield, and the American body politic has never felt the stunning shock of a nuclear weapon. While overwhelming American conventional military superiority can directly threaten a regional enemy's ability to make war on American forces, that enemy could in turn use TBM-delivered WMD capability to threaten American will to make war on him. In the media age, U.S. military action is increasingly dependent on the vicissitudes of public support—and the American public does not support long wars or heavy casualties. The public reaction to hostile use of weapons of mass destruction, covered minute by minute on CNN, might well collapse popular support for national policy.

Emotional popular reaction can sway policy either way, however. Thousands slain at Pearl Harbor stiffened national will, while eighteen dead in Mogadishu catalyzed withdrawal. Public perception of world events cannot always be accurately predicted by military and political professionals. What is certain, though, is that in our democracy, however imperfect, public perception determines public support for national military action; and if the strategic security of the United States is not perceived to be at risk, that support might well evaporate. The initiation of armed conflict is the ultimate expression of the political will of the people of a democracy, and such conflict cannot long continue unsupported by that will.19

Four Pillars of TBMD. An imminent threat to these vital centers of gravity—the military force itself, the cohesion of a regional alliance or coalition, and the political will of the American people—demands a robust response. As theater ballistic missile defense systems and doctrine have evolved since DESERT STORM, discussions of Joint TBMD capability have settled upon a common construct of "Four Pillars of TBMD"—actually, three pillars and a plinth: Active Defense, Attack Operations, and Passive Defense, all supported by a base of Battle Management Command, Control, Communications, Computers, and Intelligence (BMC4I).

TBMD active defense, the interception of theater ballistic missiles in flight, is the focus of this study; it is the centerpiece of naval TBMD capabilities. In the era of the Soviet threat, an early basic tenet of U.S. naval antiair warfare doctrine was "Shoot the archer, not the arrow." Destruction of strike aircraft offered far greater defensive leverage than attempts to individually intercept their inbound weapons. Since TBMs are ground-launched, active defense assets must face the arrows, and this constraint defines the nature of active defense operations.

Entirely aside from the mechanical and mathematical challenges posed by small, high-speed ballistic targets, active defense is innately difficult because it must start out from "behind the power curve." Planning for TBMD active defense attempts to compensate for the challenging nature of the target by working to achieve defense in-depth: early sensor cueing, followed by multiple shot opportunities for complementary interceptor systems throughout the course of an inbound missile's flight. In the Joint TBMD environment of 2008, this might include airborne laser attacks against a theater ballistic missile while it is still in boost phase (ascending, rocket motor burning); Theater Wide TBMD system attack during ascent phase (after boost, before apogee); multiple Theater Wide system interception opportunities during midcourse flight (after apogee, before reentry); and endgame attacks by area defense TBMD systems in the terminal phase (following reentry).

The defining characteristics of TBMD active defense thus include:

All of these requirements are likely to be magnified by a potential force mismatch between the number of TBMD interceptors available in theater and the number of TBMs in the enemy order of battle at the outset of hostilities.

Attack operations—aggressive interdiction of enemy TBM assets and infrastructure on the ground—have the highest potential defensive leverage and pose by far the greatest operational challenge of any pillar of TBMD. If successful, they can destroy missiles and associated WMD before launch, decimate vehicles and infrastructure to prevent further launches, and put fearful pressure on enemy TBM transporter-erector-launcher (TEL) crews to run, hide, and fire in sloppy haste—if at all. If, on the other hand, the friendly force's attack operations are relatively unsuccessful, they can entangle vast numbers of strike, tanker, and reconnaissance aircraft needed elsewhere in theater, and fruitlessly risk highly trained special operations personnel deep in enemy territory.

Along with basic passive defense measures and area defense-capable Patriot active defense, rudimentary attack operations formed the only coalition TBMD capability available during DESERT STORM; the results were decidedly mixed. Attack operations will evolve and advance by 2008, but they will still have to be able to overcome the basic challenge they face today—an extremely demanding tactical timeline.

A defining construct for attack operations is the military mnemonic of the "OODA Loop," the cycle of observe, orient, decide, act. The combatant who has sufficient information and agility to consistently operate "inside" his opponent's OODA loop, deciding and acting faster, is likely to prevail. Against TEL-mobile TBMs, the attack operations OODA cycle is very challenging. Attack assets, either airborne or ground-based, must be in position, armed, fueled, and alert when a TBM launch occurs or a TEL is detected. These assets must then be able to orient on their designated target and initiate an attack before the TEL moves and hides. The decision timeline from detection to attack is measured in minutes, and is still not consistently met, even years after Desert Storm. During the Roving Sands 95 Joint Tactical Air Operations Exercise, "even with special operations forces and a Pioneer unmanned aerial vehicle dedicated to locating [an] SS-21 battery, it successfully fired all missiles—many with [simulated] chemical warheads—against some 20 corps and division targets."20

Furthermore, although attack operations form a pillar of theater ballistic missile defense, the nature of these actions is distinctly offensive, carried out by U.S. or coalition forces on territory controlled by the enemy. Rules of engagement and command and control issues are therefore certain to be different and likely to be more constrained than those associated with active defense. While a commander may see much to be gained through the vigorous pursuit of attack operations, his actual freedom to carry them out, especially in the early days of a conflict (when active defense forces are likely to be severely challenged) may nonetheless be distinctly circumscribed.

The defining characteristics of TBMD attack operations include:

Passive defense "reduces the probability of and minimizes the effects of [TBM] attack by limiting an enemy's target acquisition capability, reducing the vulnerability of critical forces and supporting infrastructure, and improving the potential to survive and resume operations after an attack."22 The very limitations that cause regional aggressors to rely on TBM forces may tend to decrease the utility of some classic passive defense measures such as the use of decoy targets and EMCON. Hostile systems with long range, large warheads and poor CEP are most likely to be fired against large, fixed, area targets such as ports and airfields; and they are more likely still to be simply launched against cities as terror weapons attacking political centers of gravity.

Passive defense directed against an enemy's limited battle damage assessment capability, or used to enhance dissemination of early warning to civilians, has more promise. Dispersal, mission-oriented protective posture (MOPP) passive measures against WMD, inoculation of personnel against bio-agents, and temporary fortification of military facilities and individual units can be accomplished through training, doctrine, and habit.23 By their very nature, military formations are acculturated to the basic practices of passive defense, and thus are resilient and survivable if properly equipped and well-led. The same may not be said of urban civilian populations. Aggressors know this, and "soft" population centers are thus attractive as TBM targets.

Such Douhetian thinking is borne out by the results of Global Wargame '95 at Newport, Rhode Island, and Wargame 95B at the National Test Facility, Schriever Air Force Base, Colorado. Both examined major hostile TBM efforts directed against nonmilitary population centers. In a regional conflict, then, the CINC might well reap significant benefits through multinational-force coordination of passive defense efforts for population centers on his theater Defended Assets List (DAL). "It is critical to plan for and disseminate TM [theater missile] launch warning and impact area prediction to civil authorities, as well as coalition forces. . . . The theater CINC and his subordinates should consider assisting the host nation civil authorities in establishing passive defense measures for the civilian population."24

The defining characteristics of TBMD passive defense thus include:

Intelligence, early warning, and information dissemination are vital to effective passive defense. A key enabler, then, for this pillar of TBMD is the capability which also supports active defense and attack operations, the plinth beneath the pillars: battle management command, control, communications, computers and intelligence.

BMC4I for the TBMD battle encompasses far more than issues of command and control. It is indeed an "architecture," a commander's "system of systems." BMC4I seeks to overcome the greatest difficulties of TBMD—distance (great) and time (little)—by integrating focused intelligence collection, early warning, sensor cueing, defensive system response, and assessment of system effectiveness.

As TBMD systems and capabilities evolve toward 2008, the BMC4I core concept of integration becomes critical, much more than just a matter of semantics. Under the necessary developmental discipline imposed by the need for joint TBMD operations, more and more systems are achieving a degree of interoperability, either through initial design or by means of "gateways" added to older systems. "Interoperability suggests a compatibility of communications means and message formats. It produces a capability to share information directly."25

This is constructive but strictly evolutionary. The NAVCENT portion of lessons learned from the major TBMD training exercise Roving Sands 95 reads, in part: "We are still a long way from true interoperability. . . . We are not sharing data, merely conducting communications, passing tracks and overlays . . . and providing correlation."26 As envisioned for joint TBMD, BMC4I seeks to achieve the revolutionary seamless battle space implied by true integration. Thus, in the words of the Joint Staff: "Integration suggests more than just compatibility. It suggests a decision to respond to shared information in accordance with prearranged conventions and agreements. The net effect is a degree of synergy which would not otherwise occur."27

The characteristics of BMC4I for effective TBMD include:

Present Capability

The international tendencies and trends that demonstrate the need for capable theater ballistic missile defenses are compelling, as is the historical evidence of that need stemming from Desert Storm. However, before examining the TBMD-related issues of concern to a Joint Force Maritime Component Commander in 2008, it is necessary to establish "ground truth," a brief, accurate description of where U.S. active defense TBMD capabilities stand now. If a regional contingency involving a TBM-armed, WMD-capable adversary were to erupt tomorrow, what active defense systems could U.S. forces bring to the fight?

Baseline TBMD Active Defense Capability. "Today, the nation's existing TBM defense capability rests with the Patriot system and its evolving improvements."28 In the numerous exciting reports of ongoing TBMD development, it is easy for the seagoing operator to become confused by the whirl of programs and budgets, COEA studies, R&D pilot ventures, operational tests and evaluations, battle group workups, "future studies," and wargaming simulations. Thick briefing books and lengthy slide presentations show a plethora of systems in advanced stages of development, either being tested or awaiting further funding. There is, however, only one active defense weapon ready to go to war now, and that is Patriot (MIM-104).

Patriot was conceived as a mobile, all-weather air defense missile, with the XMIM-104 design specified in 1965.29 TBMD capability was not available until the deployment of Patriot Advanced Capability 1 (PAC-1) in 1988. PAC-2, the Patriot version that earned fame in the Gulf War, was not deployed until Desert Shield in 1990. Thus, the current version of the MIM-104 is a product-improved variant of an interceptor designed three decades ago.

Since Desert Storm, the missile has been modified twice, first under the Patriot quick response (QR) program (1991-1992), and more recently through the introduction of Patriot PAC-2 GEM (guidance enhanced missile) in February 1995. "We will field about 350 of these missiles, which will provide the principal improvement in our defensive capability until the Patriot Advanced Capability-3 begins deployments. . . ."30

Patriot is an area-defense weapon, intercepting TBMs in the terminal phase of their trajectory, well inside the atmosphere, and engaging them with a proximity-fuzed blast-fragmentation warhead. This type of system has inherent limitations against TBM chemical submunitions, a critical concern which drove the selection of an entirely new missile, the extended range interceptor (ERINT), using hit-to-kill technology, for Patriot PAC-3. The very short standoff range of PAC-2 intercepts also makes likely effectiveness against a barometric-fuzed nuclear TBM problematic, and destruction of very high-speed long-range TBM reentry vehicles impossible.

The system itself, consisting of headquarters, communications, and support equipment, 4-cell launching stations (LS) organized into 8-LS fire units (FU), each with its own MPQ-53 radar, and 6-FU battalions (192 missiles), is air-transportable, but not tactically mobile.31 Emplacement and relocation of fire units can be done expeditiously, but Patriot cannot "fire on the move." In effect, it is a fixed point defense system for stationary targets.

Getting Patriot into theater takes lift. Lots of lift. Movement of a PAC-2 battalion with one full missile reload takes 301 C–141 sorties.32 Moving two fire units from Germany to Israel during Desert Storm "required more than 50 C–5As, and because of bed-down limitations and refueling requirements, diverted over 120 sorties each day [through 48 hours] from other high priority lift requirements."33

Since regional deployment of Patriot means installation of U.S. military equipment and personnel on foreign soil, such deployment is unlikely prior to imminent hostilities, except in relatively developed theaters such as western Europe or northeast Asia (e.g., South Korea). Even in such "TBM-rich" environments as the Arabian Gulf, political sensitivities may impede timely deployment or reinforcement of this single U.S. TBMD active defense system.

TBMD as a "System of Systems." The relatively short range and limited mobility of the Patriot PAC-2 restricts the nature of active defense TBMD plans built around this system. Current concepts feature "enclaves" provided for specific critical assets. "The composite envelope, which is the collection of fire units producing the protected envelope and the critical assets in the area under the envelope, is designated an enclave."34 Since Desert Storm, interim TBMD enhancement efforts have involved initiatives to expand the volume of Patriot enclaves. Because the MPQ-53 radar out-ranges the MIM-104 interceptor itself, one way to enlarge an enclave would be to move fire units down-range (down the likely threat axis) from the radar supporting them. The quick response (QR) program of 1991-1992 did just this, giving the system the ability to "deploy missile launchers up to 12km from their associated fire-control radar, which enlarges the defended area."35 However, given the absolute performance limitations of the PAC-2 missile, further enhancements to the enclave concept have had to come from other areas, such as improving overall system performance through leveraging BMC4I and pursuing the synergistic effect of a "system of systems."

Enclave defense with range-limited weapons has always demanded a measure of grit from warriors. In 1775, holding Breed's Hill outside Boston, Colonel William Prescott considered the effectiveness of his smoothbore muskets, scant artillery, and limited ammunition, and told the patriots commanding the batteries, "Don't fire until you see the whites of their eyes." Today's Patriot battery commander cannot fire until the white-hot meteor of a reentering TBM streaks through the sky inbound to his enclave. At least Prescott could see the British coming for a long time. Early warning as to the size, nature, and disposition of a threat increases situational awareness and thus the efficiency of the defense. For the TBMD battle today, that warning comes from space.

Current TBMD space-based early warning depends on Defense Support Program (DSP) satellites originally deployed to detect strategic ICBM launches. Their capability against smaller TBMs with associated lower signatures is limited, but has been enhanced by USSPACECOM through the implementation of the ALERT (attack and launch early report to theater) system. "It is the operational version of prototype TM [theater missile] warning efforts developed by the tactical exploitation of national capabilities (TENCAP) office under the Talon Shield program."36 ALERT and its theater-deployed derivative, JTAGS (joint tactical ground station), process information from multiple satellites viewing a single launch, thus gaining "stereo DSP" data.

System software calculates tactical parameters such as time, latitude, longitude and altitude for comparison with known theater ballistic missile profiles. . . . Identifying the missile by means of the profile allows . . . a least-squares fit of observed altitude and downrange distance as a function of time. . . . Loft can be added to the four-state fit as a fifth parameter to permit manipulation of the profile in both altitude and downrange distance.37

The ALERT system can thus provide TBM launch time and estimated launch position (critical for attack operations), probable missile type (which may have specific engageability and warhead implications), missile state vectors (for midcourse prediction), and impact point prediction (for efficient area defense and effective passive defense).

ALERT, however, is part of the national tactical event system (TES), located in proximity to many other national capabilities near Colorado Springs, Colorado. Communications restrictions imposed by the need to filter other sensitive national systems data carried on the same nets can retard dissemination of ALERT fused data. The system can meet a warning goal of 90 seconds—but that window represents elapsed time from sensor to CINC—not sensor to TBMD shooter. Studies have shown that some enemy missiles may impact their targets before the associated ALERT cues reach the in-theater defensive assets that need them. The operational BMC4I solution to this time lag is the modular, truck-mounted, air-mobile DSP theater processing node—JTAGS.

The JTAGS system can process, fuse, and disseminate information from up to three DSP satellites (if its antennae can "see" that many of the geosynchronous sensors). Two prototypes are now operationally deployed, one in Germany and the other in South Korea. The contractor has an option for production of a further five units.38 JTAGS-processed DSP information provided in theater to an Army force projection tactical operations center (FPTOC) can enhance existing TBMD active defense capability by quickly determining which of several enclaves may be threatened by a given TBM launch, forwarding the cueing information to the correct Patriot information coordination central (ICC) vehicle at the battalion level, and thence to the individual MSQ-104 engagement control stations (ECS).

Though the MPQ-53 radar cannot directly accept external cueing data, that is a major goal of current TBMD BMC4I integration efforts. Exercises are ongoing, especially involving AEGIS SPY radar data provided to Patriot via the Navy's new cooperative engagement capability (CEC). For example, one recent test "was designed to show how CEC could help defend Europe. . . . A total of 31 simulated 'Scud' missiles were 'launched' from locations in North Africa. The launch and predicted impact point of each target, together with 'very near real-time' control data, was calculated by CEC and transmitted to [a] Patriot battery some 1,450km away. . . ."39 What must be borne in mind, however, is that such recently demonstrated capabilities are experimental rather than operational. Again quoting CENTCOM lessons learned from the recent Roving Sands 95 exercise: "The inability to real time cue and coordinate sensor data between AEGIS SPY and Patriot MPQ-53 radars limits our effectiveness."40

Implications of the Baseline. The implications for TBMD active defense failure to move beyond this baseline are far-reaching. The procurement power of such TBMD organizations as the Ballistic Missile Defense Organization (BMDO) and the Navy's Program Executive Office for Theater Air Defense, PEO (TAD), is not in doubt; but fiscal constraint has been a significant factor in Department of Defense program planning since 1985. Hence, in considering the state of U.S. theater defenses against an evolving threat, one must carefully consider what James Edward Pitts has called the "consequences of not funding."41

Regarding Patriot during Desert Storm, to paraphrase Dr. Johnson: it was not the fact that it did its job well that amazes, but the fact that it did it at all. The current system, especially when deployed with the latest guidance- enhanced missile (GEM) and supported by JTAGS, will be quite capable against that same baseline threat. However, as the first section of this chapter explained, the "baseline threat" is inexorably evolving beyond the Patriot PAC-2 engagement envelope, pushed by two great TBM trends: increasing ballistic missile system range and the frightening capability of weapons of mass destruction.

Increasing theater ballistic missile range (which can be achieved by decreasing payload, adding stages, or simply strapping on additional boosters) increases reentry velocity. Baseline defensive systems with limited standoff range, such as Patriot PAC-2, rapidly reach a point where they cannot acquire, track, launch, and achieve intercept quickly enough. The kinematics of the attacking missile have gotten inside the OODA loop of the defending interceptor. Such absolute physical limitations can only be overcome by fielding a different system; this fact has compelled development of PAC-3 ERINT and even longer range systems such as SM2 Block IVA Navy Area, Army THAAD (theater high altitude area defense), and the very long-range Navy Theater Wide (NTW, using the SM3 missile) system. None is a substitute for another; all are complementary components of an evolving active defense family-of-systems.

In addition to providing robust capability against long-range, high-speed systems, or shorter range, high-apogee (lofted trajectory) TBMs, exoatmospheric TBMD systems such as THAAD and NTW provide an essential capability against weapons of mass destruction, which—to repeat—baseline systems do not. Even a highly lethal area defense hit-to-kill design such as PAC-3 will cause the release of some WMD components into the air upon intercept consummation. Only the Theater Wide defense systems have the ability to make the kill in space, forcing any surviving WMD materials to careen into the atmosphere unshielded.

Theater Wide systems also extend the battle space, a primary goal of any commander, while the baseline system does not; indeed, the current baseline system surrenders not only battle space, but also vital intelligence to the enemy. The fixed enclaves and point-defense limitations of PAC-2 announce clearly which assets on the DAL the CINC intends to defend, and thus, conversely, which he is willing to sacrifice.

The CINC may not even be able to make that admittedly difficult choice expeditiously, for political sensitivities may constrain his ability to emplace TBMD assets before the onset of hostilities. Once conflict commences, strategic lift sensitivities could inhibit his ability to reactively deploy active defenses even more. "When a crisis occurs, the real-time decision to devote scarce airlift assets to move a Patriot battalion instead of infantry or artillery equipment will be difficult and pressing."42

If the TBM threat continues to evolve, then joint TBMD capability must progress beyond the baseline. In the military world, as in the natural world, over-specialization is an invitation to catastrophe. A robust response to an evolving threat requires diverse capabilities fully integrated through a common BMC4I architecture. During the crucial early days of a regional contingency, when "the Navy kicks open the door and holds it open for the heavy land forces," the TBMD active defense capabilities most likely to be picked from that diverse palette by the Joint Force Maritime Component Commander will be naval.43 If the U.S. military moves resolutely beyond the baseline, the JFMCC will have flexible, deployable, multitiered naval TBMD capability available by 2008. The projected characteristics of those specific systems are the subject of the next section.

Naval TBMD Active Defense Capabilities to 2008

"The Navy TBMD system shall be comprised of two tiers, which provides for an Area (lower tier) defense and Theater Wide (upper tier) defense. The Naval TBMD system shall provide capability against the full range of TBM threats for protection of joint forces, sea and air lines of communications, command and control facilities, vital political and military assets, supporting infrastructure, and population centers."44 Navy Area TBMD will be provided by the SM2 Block IVA interceptor, while Navy Theater Wide (NTW) will likely depend on the SM3 missile, carrying an infrared-homing kinetic warhead. Sensor capability will be built around the AEGIS-organic SPY radar, with off-board cueing from JTAGS-type fused DSP data. Because of the highly automated, highly integrated, self-contained nature of modern warships, much of the framework for the projected joint TBMD BMC4I architecture is already in place on AEGIS combatants. As stated in chapter I of this study, it is presumed that the architecture will be fully functional by 2008.

Navy Area TBMD. The SM2 Block IVA interceptor represents the latest stage in the remarkable evolution of the Navy's standard missile, a weapon whose roots reach back to the TARTAR and TERRIER offspring of the BUMBLEBEE antiair warfare program of the 1950s. Navy Area is one of the Ballistic Missile Defense Organization "core" TBMD systems, and thus (along with Patriot PAC-3, THAAD, and Navy Theater Wide) has a great deal of developmental and bureaucratic momentum. A contingency capability of two Navy Area AEGIS cruisers with at least 35 SM2 Block IVA missiles will put to sea by the end of the century.45

The Block IVA missile itself is a boosted, high-mach, long-range, solid-fuel interceptor with "dual mode" terminal homing (IR primary and semi-active RF secondary) and a blast-fragmentation warhead specifically enhanced for the TBMD role. The combination of precise guidance (which increases the chance of a direct "skin-to-skin" hit or very near miss) with a powerful explosive warhead makes this interceptor extremely potent.46 Proximity-fuzed, it therefore does not suffer the one major drawback of kinetic-energy hit-to-kill systems—their all-or-nothing gamble on flawless guidance and successful terminal homing.

Like Patriot PAC-3, SM2 Block IVA will be multimission capable, lethal against cruise missiles and manned aircraft in addition to TBMs. However, as shown during Roving Sands 95, its "defended footprint" will be far larger than that of PAC-3, allowing a rudimentary layered defense using only "lower-tier" systems if Patriot is in place in a littoral enclave. Against a simulated 600km-range TBM, a Navy Area engagement at 120km is possible many more times than is a PAC-3 intercept against the same target.47 Maximum intercept altitude, which is critical against WMD warheads, is also considerably greater, at 35km—a height of over 113,000 feet.48 Additionally, it should be noted that for short-range TBMs with apogees (highest point of ballistic trajectory) within the atmosphere, Navy Area will be the only naval active defense system capable of engaging, because the Navy Theater Wide SM3 interceptor functions outside the atmosphere.

Such figures, however, need to be evaluated carefully. The defended footprint of any area defense TBMD interceptor decreases as the velocity of the incoming TBM target increases. Ballistic missile terminal velocity is a function of system range; so the longer the range of the enemy system, the smaller the area that can be defended by lower tier systems. For example, against a 900km-range TBM, Navy Area engagement range drops to 65km, or approximately thirty-five nautical miles—ranges familiar to shipboard operators of early fleet AW SM2 variants.49

The thoughtful reader must beware of oversimplification. The concept of a "defended footprint"—in effect a Navy Area enclave—represents a complex geometry dependent on many factors, including TBM range and related terminal velocity, radar cross-section (RCS), and the spatial relationship between the AEGIS ship and the asset it is defending. Furthermore, in a littoral environment, Navy Area systems will have to provide greater coverage than equivalent ground-based systems because of the prospect of a shoal-water "buffer" between the TBMD ship and the DAL target it is defending. Area defense systems generally benefit from collocation with the assets they are defending, but it often will be difficult for a Navy Area ship to patrol in proximity to the asset it is assigned to protect. Until ground-based systems are emplaced in theater, Navy Area ships will need all the reach they can get to "hold open the door."

Well forward, defending an amphibious objective area or other military assets against short-range TBM threats, that inland Navy Area "reach" will be considerable. Defending political or population targets far from the main military engagement, however, not only takes multimission ships and tethers them to single targets; it also markedly shrinks the footprint area and engagement altitude of their defended envelopes against just those hostile systems (long-range TBMs) most likely to be employed with WMD, weapons which tend to negate the value of close-in point defense. This long-range, politically targeted WMD-capable threat postulated for 2008 drives the need for another layer of protection to complement the versatile, capable, but limited scope of Navy Area. That seagoing "upper tier" capability is Navy Theater Wide.