Congressional Budget Office - March 1997


Annual Savings							Five-Year
Savings from			(Millions of dollars)	   	Cumulative
the 1997 Plan		1998	1999	2000	2001	2002	Total

Budget Authority	300	290	1,036	1,089	673	3,388

Outlays			 61	148	388	680	822	2,099

The D5 missile, also called the Trident II missile, is the most accurate and powerful submarine-launched ballistic missile (SLBM) in the U.S. inventory. The result of more than 15 years of research and development, it is the keystone of the Navy's plan to modernize its ballistic missile force. Because of its accuracy and the size of its warheads, the D5 is the first submarine-launched missile that is capable of destroying very hard (or counterforce) targets such as missile silos and command bunkers. That capability has allowed the Navy to assume some of the counterforce missions that previously could be carried out only by the Air Force's land-based intercontinental ballistic missiles and long-range bombers.

The Administration's plan, which reflects the results of the recent Nuclear Posture Review, assumes that the Navy will reduce the Trident force to 14 submarines by 2003, when the United States must fully implement the second Strategic Arms Reduction Treaty (START II). Each submarine will carry 24 D5 missiles. The Navy currently has eight Trident submarines that carry C4 missiles and by 1998 will have a fleet of 10 additional Tridents armed with the more modern D5 missile. To achieve its 14-boat fleet, the Navy will retire the four oldest C4-capable submarines in 2002 and 2003 and convert the other four to carry D5 missiles (one each in 2000, 2001, 2004, and 2005). To support that force, the Navy plans to buy a total of 434 D5 missiles. It has already bought 350 missiles and plans to purchase seven more in 1998 and a total of 84 more through 2005. To keep the number of U.S. warheads near the ceiling allowed by START II, which limits the number of warheads on submarine-launched ballistic missiles to 1,750, the Navy will probably reduce the number of warheads per missile from eight to five (for a total of 1,680 warheads).

This option would terminate D5 production after 1997 and retire all eight C4 submarines. The Navy would have 350 D5 missiles--three more than the number that it says it would need to support a 10-submarine force in light of its recent decision to reduce the number of D5 test flights to four a year. Like the Administration's plan, however, this option would not retire the C4 submarines until after the turn of the century, both to encourage Russia's compliance with START II and to retain the flexibility for the United States to remain at higher START I levels if Russia does not comply. To keep warheads at the level planned by the Administration under START II, this option would increase the number of warheads on each missile from five to seven.

Relative to the Administration's plan, this option would save $300 million in budget authority in 1998 and $3.4 billion through 2002. Outlays would be re-duced by $2.1 billion through 2002. Most of those savings would be from canceling missile production. In addition, retiring C4 submarines in 2000 and 2001 rather than upgrading them would save about $400 million to $500 million in each of those years. This option would create significant savings beyond 2002 because it would operate fewer submarines and avoid the cost of modifying C4 submarines and purchasing D5 missiles.

Several drawbacks are associated with terminating production of D5 missiles. Increasing the number of warheads per missile from five to seven would reduce the range of the missiles by roughly 20 percent. That would limit the areas of the ocean in which submarines could operate, thereby making the fleet more vulnerable. Furthermore, it would reduce the targeting flexibility of the force because missiles with fewer warheads can cover more widely dispersed targets. Also, requiring the Navy to deploy D5 missiles with seven warheads would constrain the United States' ability to in-crease sharply the size of its SLBM force by adding back the extra warheads if Russia broke out of START II or never ratified the treaty, a central concern of some critics of this option. (See Congressional Budget Office, Rethinking the Trident Force, July 1993, for more details about the effects of this and other options for reducing the costs of the Trident force.) In addition, reducing the force from 14 to 10 submarines may increase its vulnerability to attack by Russia's antisubmarine forces. Critics also worry that terminating the production of the D5 missile early would leave the United States unable to produce new SLBMs without an expensive rebuilding program.

Nevertheless, terminating D5 production may be acceptable given the marked reduction in the chances of nuclear war between the superpowers. In that environment, the capability retained under this option for Trident submarines to destroy hardened targets may be judged sufficient to deter nuclear war. Although the range of the missiles and the size of submarine patrol areas would be smaller under this option than under the Administration's plan, they would still exceed those planned during the Cold War when Russia's antisubmarine capability was greater and the United States intended to deploy the D5 with eight large warheads (W-88s).

The targeting flexibility given up by this option might not significantly reduce the ability of the SLBM force to deter nuclear war. It is not clear that the force of 1,680 warheads that the Administration plans to deploy on its Trident fleet under START II will deter an adversary more effectively if they are deployed on 336 missiles rather than on the 240 called for in this option. The diminished likelihood of nuclear war with Russia may also have weakened the rationale for the United States to deploy only five warheads on each D5 missile in order to retain its ability to increase U.S. nuclear forces rapidly. Moreover, the United States could increase the number of warheads on land-based ballistic missiles and bombers if Russia violated START II. Finally, supporters of this option would argue that the aerospace companies involved in refurbishing the Minuteman III and building boosters for space launchers will maintain enough skilled workers so that production of a new SLBM could be started in time to replace the missiles lost as Trident submarines begin to retire during the next century.