Washington, D.C. – November 12, 2024 – The United Kingdom is modernizing its stockpile of nuclear weapons and delivery systems, as detailed today in the Federation of American Scientists latest edition of its Nuclear Notebook, “United Kingdom Nuclear Forces, 2024”. The researchers estimate that the United Kingdom has maintained its stockpile of 225 nuclear warheads and predict an eventual increase based on shifting posture to counter Russia, modernization, and alliance efforts. The Notebook is published in the Bulletin of the Atomic Scientists and available here.

“Budget overruns remain a constraint for the UK nuclear modernization program, significant parts of which are done in close collaboration with the United States, and efforts are underway to expand the nuclear warhead stockpile,” observes Hans Kristensen, Director of the FAS Nuclear Information Project and one of the Nuclear Notebook authors.

Modernization and nuclear infrastructure construction

The United Kingdom is replacing its sole nuclear platform––the aging Vanguard-class ballistic missile submarines (SSBNs)––with the new Dreadnought-class that is currently under construction. 

Additionally, the FAS report includes satellite imagery of ongoing construction at the Atomic Weapons Establishment (AWE) facilities at Aldermaston and Burghfield, including a new warhead assembly facility, enriched uranium storage facility, and plutonium manufacturing facility. 

Challenges for the future

Budget overruns and delays in construction continue to be one of the biggest issues for the United Kingdom’s nuclear program. Projected costs for the UK Navy have gone up by 41 percent due to the Dreadnought SSBN program. Delays in this program could threaten the Navy’s ability to maintain their Continuous At-Sea Deterrent (CASD), as it would put additional stress on the Vanguard fleet that has already been pushed past its service life. Nuclear infrastructure projects, including the MENSA warhead facility, are also behind schedule and over-budget. 

Collaboration with the United States

Upgrades at RAF Lakenheath discovered by the Notebook authors signal the return of the United States Air Force nuclear mission to the United Kingdom, although it is unlikely that US nuclear weapons will be permanently stored on UK soil in peacetime. The arrival of the F-35A Lightning II, capable of carrying B61-12 gravity bombs, US budgetary indicators for special storage upgrades, and the construction of a new “surety” dormitory for US Airmen at RAF Lakenheath all indicate preparations for the potential return of US nuclear weapons which have been absent in the United Kingdom since 2008. 

The Notebook also outlines cooperation between the UK and US Navy on missile tests. This year, UK ballistic missile submarines conducted test fires off the coast of Cape Canaveral, Florida, and US laboratories evaluated and provided measurements for the test effort.

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ABOUT THE NUCLEAR NOTEBOOK 

The FAS Nuclear Notebook, co-authored by Hans M. Kristensen, Matt Korda, Eliana Johns, and Mackenzie Knight, is an effort by the Nuclear Information Project team published bi-monthly in the Bulletin of the Atomic Scientists. The joint publication began in 1987. FAS, formed in 1945 by the scientists who developed the nuclear weapon, has worked since to increase nuclear transparency, reduce nuclear risks, and advocate for responsible reductions of nuclear arsenals and the role of nuclear weapons in national security.

This latest issue follows the release of the 2024 India Nuclear Notebook. The next issue will focus on the United States. More research is located at FAS’s Nuclear Information Project.

The Federation of American Scientists’ work on nuclear transparency would not be possible without generous support from the Carnegie Corporation of New York, Longview Philanthropy, the Jubitz Foundation, the New-Land Foundation, Ploughshares, the Prospect Hill Foundation, and individual donors.

ABOUT FAS

The Federation of American Scientists (FAS) works to advance progress on a broad suite of contemporary issues where science, technology, and innovation policy can deliver dramatic progress, and seeks to ensure that scientific and technical expertise have a seat at the policymaking table. Established in 1945 by scientists in response to the atomic bomb, FAS continues to work on behalf of a safer, more equitable, and more peaceful world.

Washington, D.C. – September 6, 2024 – The Federation of American Scientists today released the latest India edition of the Nuclear Notebook, published in the  Bulletin of the Atomic Scientists and available here. The authors, Hans Kristensen, Matt Korda, Eliana Johns, and Mackenzie Knight, estimate that India has produced enough weapons-grade plutonium for up to 210 nuclear warheads but has likely assembled closer to 172. Along with its growing arsenal, India is developing at least five new weapon systems and several new delivery platforms. Seeking to address security concerns with both Pakistan and China, India appears to be taking steps to increase the readiness of its arsenal, including “pre-mating” some of its warheads with missiles in canisters.

SSBNs and MIRVs

This Nuclear Notebook provides an overview of India’s nuclear modernization, documenting the development of new land and sea-based missiles, the retirement of older nuclear-capable systems, and the commissioning of India’s second indigenous nuclear-powered ballistic missile submarine (SSBN). The authors also analyze India’s significant progress in developing its next generation of land-based missiles with the capability to launch multiple independently targetable reentry vehicles (MIRVs).

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ABOUT THE NUCLEAR NOTEBOOK 

The FAS Nuclear Notebook, co-authored by Hans M. Kristensen, Matt Korda, Eliana Johns, and Mackenzie Knight, is published bi-monthly in the Bulletin of the Atomic Scientists. The joint publication began in 1987. FAS, formed in 1945 by the scientists who developed the nuclear weapon, has worked since to increase nuclear transparency, reduce nuclear risks, and advocate for responsible reductions of nuclear arsenals and the role of nuclear weapons in national security.

This latest issue follows the release of the 2024 North Korea Nuclear Notebook. The next issue will focus on the United Kingdom. More research is located at FAS’s Nuclear Information Project.

The Federation of American Scientists’ work on nuclear transparency would not be possible without generous support from the Carnegie Corporation of New York, Longview Philanthropy, the Jubitz Foundation, the New-Land Foundation, Ploughshares, the Prospect Hill Foundation, and individual donors.

ABOUT FAS

The Federation of American Scientists (FAS) works to advance progress on a broad suite of contemporary issues where science, technology, and innovation policy can deliver dramatic progress, and seeks to ensure that scientific and technical expertise have a seat at the policymaking table. Established in 1945 by scientists in response to the atomic bomb, FAS continues to work on behalf of a safer, more equitable, and more peaceful world. More information at fas.org.

North Korea continues to modernize and grow its nuclear weapons arsenal

Washington, D.C. – July 15, 2024 – The Federation of American Scientists today released the North Korea edition of the Nuclear Notebook, published in the  Bulletin of the Atomic Scientists and available here. The authors, Hans Kristensen, Matt Korda, Eliana Johns, and Mackenzie Knight, estimate that North Korea may have produced enough fissile material to build up to 90 nuclear warheads, but the famously opaque country has likely assembled fewer than that—potentially around 50. This is not a significant change from previous estimates (2021, 2022) but follows the trendline researchers are tracking. North Korea’s abandonment of a no-first-use policy coincides with the country’s recent efforts to develop tactical nuclear weapons.

Warhead Preparation and Delivery

While its status remains unclear, North Korea has developed a highly diverse missile force in all major range categories. In this edition of the Nuclear Notebook, FAS researchers documented North Korea’s short-range tactical missiles, sea-based missiles, and new launch platforms such as silo-based and underwater platforms Additionally, FAS researchers provided an overview of North Korea’s advancements in solid-fuel missile technology, which will improve the survivability and mobility of its missile force.

“Since 2006, North Korea has detonated six nuclear devices, updated its nuclear doctrine to reflect the irreversible role of nuclear weapons for its national security, and continued to introduce a variety of new missiles test-flown from new launch platforms,” says Hans Kristensen, director of FAS’s Nuclear Information Project. 

The size and composition of North Korea’s nuclear stockpile depends on warhead design and the number and types of launchers that can deliver them.

Disco Balls, Peanuts, and Olives

Researchers informally refer to North Korea’s nuclear warhead designs as the disco ball, peanut, and olive based on their appearance in North Korean state media. These images, taken from this recent issue of the North Korea Nuclear Notebook, show supposed warhead designs, including a single-stage implosion device (nicknamed “disco-ball”), a new miniaturized warhead called the Hwasan-31 (nicknamed “olive”), and a two-stage thermonuclear warhead (nicknamed “peanut”).  

Caption: Images from the Nuclear Notebook: North Korea, 2024. Top left “disco ball”, top right “olive”, bottom left “peanut”. (Source: Federation of American Scientists).

While North Korea’s warhead design and stockpile makeup are not verifiable, it is possible that most weapons are single-stage fission weapons with yields between 10 and 20 kilotons of TNT equivalent, akin to those demonstrated in the 2013 and 2016 tests. A smaller number could be composite-core single-stage warheads with a higher yield.

The Hwasan-31, first showcased in 2023, demonstrates North Korea’s progress towards developing and fielding short-range, or tactical, nuclear weapons. In addition to the development and demonstration of new long-range strategic nuclear-capable missiles, the pursuit of tactical nuclear weapons appears intended to provide options for nuclear use below the strategic level and to strengthen North Korea’s regional deterrence posture.

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ABOUT THE NUCLEAR NOTEBOOK 

The FAS Nuclear Notebook, co-authored by Hans M. Kristensen, Matt Korda, Eliana Johns, and Mackenzie Knight, is published bi-monthly in the Bulletin of the Atomic Scientists. The joint publication began in 1987. FAS, formed in 1945 by the scientists who developed the nuclear weapon, has worked since to increase nuclear transparency, reduce nuclear risks, and advocate for responsible reductions of nuclear arsenals and the role of nuclear weapons in national security.

This latest issue follows the release of the 2024 United States Nuclear Notebook. The next issue will focus on India. More research is located at FAS’s Nuclear Information Project.

ABOUT FAS

The Federation of American Scientists (FAS) works to advance progress on a broad suite of contemporary issues where science, technology, and innovation policy can deliver dramatic progress, and seeks to ensure that scientific and technical expertise have a seat at the policymaking table. Established in 1945 by scientists in response to the atomic bomb, FAS continues to work on behalf of a safer, more equitable, and more peaceful world. More information at fas.org.

The Federation of American Scientists has released its annual estimate of the size and makeup of Russia’s nuclear forces. The total number of nuclear warheads are now estimated to include 4,380 stockpiled warheads for operational forces, as well as an additional 1,200 retired warheads awaiting dismantlement, for a total inventory of 5,580 warheads.

Despite modernization of Russian nuclear forces and warnings about an increase of especially shorter-range non-strategic warheads, we do not yet see such an increase as far as open sources indicate. For now, the number of non-strategic warheads appears to be relatively stable with slight fluctuations. Although our new estimate of this category is lower than last year, that is not because of an actual decrease in the force level but because we have finetuned assumptions about the number of warheads assigned to Russian non-strategic nuclear forces. Our new estimate of roughly 1,558 non-strategic warheads is well within the range of 1,000-2,000 warheads estimated by the U.S. Intelligence Community for the past several years. 

While Russia’s nuclear statements and threatening rhetoric are of great concern, Russia’s  nuclear arsenal and operations have changed little since our 2023 estimates beyond the ongoing modernization. In the future, however, the number of warheads assigned to Russian strategic forces may increase as single-warhead missiles are replaced with missiles equipped with multiple warheads. If the New START treaty is not replaced with a new agreement, both Russia and the United States could potentially increase the number of deployed warheads.

Also in the Nuclear Notebook: Russian nuclear forces, 2024, is our latest analysis on Russian force modernization and strategy:

• Russian nuclear force modernization, intended to replace Soviet-era missiles, aircrafts, and submarines with new systems, continues at a steady pace.
• Modernization of road-mobile intercontinental ballistic missiles is essentially complete with focus shifting to modernizing silo-based missiles.
• New strategic and non-strategic submarines continue to replace Soviet-era models but with enhanced nuclear weapon systems.
• Upgrades and some reproduction of Soviet-era strategic bombers continue with new long-range cruise missiles. 
• News leaks seem to indicate that Russia might be developing a nuclear-armed  anti-satellite weapon which, if deployed in the future, would violate the Outer Space Treaty. 
• Upgrades of nuclear weapons storage facilities are underway at several bases to accommodate the weapons for modernized forces. 
• Because Russian conventional forces have been significantly depleted and their effectiveness questioned by the war in Ukraine, nuclear forces will likely be seen as important to compensate for that weakness.

The FAS Nuclear Notebook, published in the Bulletin of the Atomic Scientists, is widely considered the most accurate public source for information on global nuclear arsenals for all nine nuclear-armed states. 

ABOUT FAS
The Federation of American Scientists (FAS) works to advance progress on a broad suite of contemporary issues where science, technology, and innovation policy can deliver dramatic progress, and seeks to ensure that scientific and technical expertise have a seat at the policymaking table. Established in 1945 by scientists in response to the atomic bomb, FAS continues to work on behalf of a safer, more equitable, and more peaceful world. More information at fas.org.

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This research was carried out with generous contributions from the New-Land Foundation, Ploughshares Fund, the Prospect Hill Foundation, Longview Philanthropy, and individual donors.

The Federation of American Scientists’ Nuclear Information Project, a component of the Federation’s Global Risk program, today released its latest assessment of China’s growing nuclear arsenal: the 2024 Nuclear Notebook on Chinese Nuclear Forces. The 24-page report, published in the Bulletin of Atomic Scientists, includes details on China’s nuclear weapons arsenal, including types of weapons, delivery vehicles, operations, and, importantly, questions that can help determine the reliability and accuracy of projections about the future growth of China’s nuclear capabilities.

The Notebook comes at a critical time for U.S. analysis and policy debates regarding China’s nuclear forces and the appropriate U.S. and allied response. In October 2023, the Pentagon released its annual report to Congress on Military and Security Developments Involving the People’s Republic of China. This report preceded the release of both the Strategic Posture Commission report and the State Department’s International Security Advisory Board report on Nuclear Deterrence in a World of Nuclear Multipolarity. Within the U.S. government, military, and national security community, analysts are evaluating the implications of China’s growing nuclear force for nuclear deterrence, global stability, and U.S. security commitments in East Asia, Europe, and beyond. 

What about the DOD’s numbers?

Meanwhile, the 2024 Nuclear Notebook on Chinese nuclear forces comes on the heels of a news report from Bloomberg that suggest corruption in China’s military procurement program may have resulted in the production or delivery of nuclear-tipped missiles and missile silos that do not operate properly. Reports about China’s corruption are not new, but the potential impact on the unprecedentedly rapid projected growth of China’s nuclear forces has not been previously reported, nor has it been reflected in reports, testimony, or statements by top Administration, defense, or intelligence officials.

Given the potential implications of the Bloomberg report, FAS sent a letter to Secretary of Defense Lloyd Austin asking whether the reported intelligence about the reliability of China’s missile force was known to the authors of DOD reports on China’s nuclear program and, if so, why they were not reflected in reports sent to Congress. As one of the most authoritative non-governmental sources on global nuclear forces, FAS has a unique interest in ensuring that its reports are objective and reflect the full extent of government and non-governmental expert understanding of nuclear arsenals worldwide.

2024 Nuclear Notebook: Key findings on China’s nuclear forces

Analyzing and estimating China’s nuclear forces is challenging, particularly given the relative lack of state-originating data and the tight control of messaging surrounding the country’s nuclear arsenal and doctrine. Like most other nuclear-armed states, China has never publicly disclosed the size of its nuclear arsenal or much of the infrastructure that supports it. The analyses and estimates made in the Nuclear Notebook are derived from a combination of open sources, including (1) state-originating data (e.g. government statements, declassified documents, budgetary information, military parades, and treaty disclosure data), (2) non-state-originating data (e.g. media reports, think tank analyses, and industry publications), and (3) commercial satellite imagery. From this information, FAS has tracked the significant expansion of China’s ongoing nuclear modernization program. Key findings from the 2024 FAS assessment on Chinese nuclear forces include: 

1. China’s nuclear expansion is among the largest and most rapid modernization campaigns of the nine nuclear-armed states.
2. FAS estimates that China has produced a stockpile of approximately 500 nuclear warheads, with 440 warheads available for delivery by land-based ballistic missiles, sea-based ballistic missiles, and bombers. 
3. The latest Pentagon projection appears to apply the same growth rate of new warheads added to the stockpile between 2019 and 2021 to the subsequent years until 2035. FAS assesses that this projected growth trajectory is feasible but depends significantly upon many uncertain factors and assumptions.
4. China has continued to develop its three new missile silo fields for solid-fuel intercontinental ballistic missiles (ICBMs), expand the construction of new silos for its liquid-fuel DF-5 ICBMs, and has been developing new variants of ICBMs and advanced strategic delivery systems. 
5. China has further expanded its dual-capable DF-26 intermediate-range ballistic missile (IRBM) force, which appears to have completely replaced the medium-range DF-21 in the nuclear role.
6. China has been refitting its Type 094 ballistic missile submarines with the longer-range JL-3 submarine-launched ballistic missile (SLBM). 
7. China has recently reassigned an operational nuclear mission to its bombers and is developing an air-launched ballistic missile (ALBM) that might have nuclear capability.

This research was carried out with generous contributions from the New-Land Foundation, Ploughshares Fund, the Prospect Hill Foundation, Longview Philanthropy, and individual donors.

The FAS Nuclear Notebook is one of the most widely sourced reference materials worldwide for reliable information about the status of nuclear weapons and has been published in the Bulletin of the Atomic Scientists since 1987. The Nuclear Notebook is researched and written by the staff of the Federation of American Scientists’ Nuclear Information Project: Director Hans M. Kristensen, Senior Research Fellow Matt Korda, Research Associate Eliana Johns, and Scoville Peace Fellow Mackenzie Knight.

This issue’s column examines the current state of global nuclear sharing arrangements, which include non-nuclear countries that possess nuclear-capable delivery systems for employment of a nuclear-armed state’s nuclear weapons.

Read the full “Nuclear weapons sharing, 2023” Nuclear Notebook in the Bulletin of the Atomic Scientists, or download a PDF using the button on the left side of this page. The complete archive of FAS Nuclear Notebooks can be found here.

This research was carried out with generous contributions from the New-Land Foundation, Ploughshares Fund, the Prospect Hill Foundation, Longview Philanthropy, and individual donors.

The FAS Nuclear Notebook is one of the most widely sourced reference materials worldwide for reliable information about the status of nuclear weapons and has been published in the Bulletin of the Atomic Scientists since 1987. The Nuclear Notebook is researched and written by the staff of the Federation of American Scientists’ Nuclear Information Project: Director Hans M. Kristensen, Senior Research Fellow Matt Korda, and Research Associate Eliana Johns.

This issue’s column finds that Pakistan is continuing to gradually expand its nuclear arsenal with more warheads, more delivery systems, and a growing fissile material production industry. We estimate that Pakistan now has a nuclear weapons stockpile of approximately 170 warheads.

Read the full “Pakistan Nuclear Weapons, 2023” Nuclear Notebook in the Bulletin of the Atomic Scientists, or download a PDF using the button on the left side of this page. The complete archive of FAS Nuclear Notebooks can be found here.

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This research was carried out with generous contributions from the New-Land Foundation, Ploughshares Fund, the Prospect Hill Foundation, Longview Philanthropy, and individual donors.

The FAS Nuclear Notebook is one of the most widely sourced reference materials worldwide for reliable information about the status of nuclear weapons and has been published in the Bulletin of the Atomic Scientists since 1987. The Nuclear Notebook is researched and written by the staff of the Federation of American Scientists’ Nuclear Information Project: Director Hans M. Kristensen, Senior Research Fellow Matt Korda, and Research Associate Eliana Johns.

This issue’s column reviews the status of France’s nuclear arsenal and finds that the stockpile of approximately 290 warheads has remained stable in recent years. However, significant modernizations regarding ballistic missiles, cruise missiles, submarines, aircraft, and the nuclear industrial complex are underway.

Read the full “French Nuclear Weapons, 2023” Nuclear Notebook in the Bulletin of the Atomic Scientists, or download a PDF using the button on the left side of this page. The complete archive of FAS Nuclear Notebooks can be found here.

The FAS Nuclear Notebook is one of the most widely sourced reference materials worldwide for reliable information about the status of nuclear weapons, and has been published in the Bulletin of the Atomic Scientists since 1987. The Nuclear Notebook is researched and written by the staff of the Federation of American Scientists’ Nuclear Information Project: Director Hans M. Kristensen, Senior Research Associate and Project Manager Matt Korda, and Research Associate Eliana Johns.

This issue’s column examines Russia’s nuclear arsenal, which includes a stockpile of approximately 4,489 warheads. Of these, some 1,674 strategic warheads are deployed on ballistic missiles and at heavy bomber bases, while an approximate additional 999 strategic warheads, along with 1,816 nonstrategic warheads, are held in reserve. The Russian arsenal continues its broad modernization intended to replace most Soviet-era weapons by the late-2020s.

Read the full “Russian Nuclear Weapons, 2023” Nuclear Notebook in the Bulletin of the Atomic Scientists, or download a PDF using the button on the left side of this page. The complete archive of FAS Nuclear Notebooks can be found here.

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[Updated] The Biden administration yesterday afternoon declassified the number of nuclear weapons the United States possesses. The act reverses the secrecy of the Trump administration, which denied release of the number for three years, and restores the nuclear transparency of the Obama administration.

FAS’ Steve Aftergood asked for this information in March 2021. We have still not received an official response.

Although a victory for nuclear transparency, the data shows only very limited nuclear weapons reductions in recent years – a stark reminder of the international nuclear climate, domestic policies, and that a lot more work is needed to reduce nuclear dangers.

Stockpile Numbers

According to the new data, the United States possessed a total of 3,750 nuclear warheads in the Department of Defense nuclear weapons stockpile as of September 2020. That number is only 50 warheads less than our estimate of 3,800 warheads from early this year.

The 3,750-warhead number is only 72 warheads fewer than in September 2017, the last number made available before the Trump administration closed the books.

That reduction is by any measure mediocre. In its announcement about the new stockpile numbers, the US Department of State highlights that the current stockpile of 3,750 warheads “represents an approximate 88 percent reduction in the stockpile from its maximum (31,255) at the end of fiscal year 1967, and an approximate 83 percent reduction from its level (22,217) when the Berlin Wall fell in late 1989.” While that is true and an amazing accomplishment, the fact remains that the vast majority of that reduction happened in two phases during the H.W. Bush and W. Bush administrations. Since 2008 the reduction has been slow and limited. The trend is that the reduction is decreasing and leveling out.

A peculiar revelation in the new data is that it shows that the stockpile increased by 20 warheads between September 2018 and September 2019 when Trump was in office. The increase is not explained but one possibility is that it reflects the production of the new W76-2 low-yield warhead that the Trump administration rushed into production in response to what it said was Russia’s plans for first-use of tactical nuclear weapons. The first W76-2 was produced in February 2019, NNSA was scheduled to deliver all the warheads by end of Fiscal Year 2019, but the W76-2 wasn’t completed until June 2020. Arkin and Kristensen reported in January 2020 that the first W76-2s had been deployed, which was later confirmed by the Pentagon.

It is possible (but unconfirmed) that the 20-warhead stockpile increase between 2018 and 2019 was caused by production of the Trump administration’s W76-2 low-yield Trident warhead. Image: NNSA.

The Trump administration’s brief increase of the stockpile is only the second time the United States has increased its number of nuclear warheads since the Cold War. The first time was in 1995-1996 when the Clinton administration increased the stockpile by 107 warheads. Since the W76-2 production continued after September 2019, the increase of 20 warheads should not be misinterpreted as being the final number of W76-2 warheads. After the 2018-2019 increase, the stockpile number dropped again by 55 warheads.

Update: Another possibility for the brief stockpile increase is that a small number of retired warheads were returned to the stockpile. This could potentially be B83-1 bombs that the Trump administration decided to retain instead of retiring with the fielding of the B61-12. It could potentially also be retired warheads brought in as feedstock for new weapon systems such as the planned nuclear sea-launched cruise missile. We just don’t know at this point.

Apparently, the nuclear modernization program supported by both Republicans and most Democrats, will result in significant additional reductions of the stockpile. In 2016, the former head of the Navy’s Strategic Systems Program, Vice Admiral Terry Benedict, said that once the W76-1 warhead production was completed by the end of FY2019, the W76-0 warheads that had not been converted to W76-1 would be retired and the total number of W76 warheads in the stockpile decrease by nearly 50%.

At the same time, the Pentagon’s Principal Deputy Assistant Secretary of Defense for Nuclear, Chemical, and Biological Defense Programs, Arthur T. Hopkins, told Congress that production and fielding of the B61-12 bomb would “result in a nearly 50 percent reduction in the number of nuclear gravity bombs in the stockpile” and “facilitate the removal from the stockpile of the last megaton-class weapon––the B83-1.”

Production of the W76-1 has now been completed but the promised reduction is not yet visible in the stockpile data – unless the excess warheads were gradually removed during the production years. The B61-12 has not been fielded yet so the gravity bomb reduction presumably will not happen until the mid-2020s.

Whatever the number of the additional stockpile reduction is, it is not planned to be nice to Kremlin and Beijing but because the US military doesn’t need the excess warheads anymore. Whether Russia and China’s nuclear increases will cause the Biden administration to change the plan outlined by Benedict and Hopkins will be decided by the Nuclear Posture Review.

Dismantlement Numbers

The data also shows that the United States as of September 2020 had about 2,000 retired warheads in storage awaiting dismantlement. Retired warheads are owned by the Department of Energy and not part of the DOD stockpile.

That number matches the available data. Former Secretary of State John Kerry said in 2015 that there were about 2,500 retired weapons left (as of September 2014). Since then, 1,432 warheads have been dismantled and an additional 967 weapons retired, which would leave just over 2,000 warheads in the dismantlement queue.

Approximately 2,000 retired warheads away dismantlement, including the B83 megaton gravity bomb. More are expected to follow during the next decade. Image: NNSA.

In our estimate from early this year, we thought the dismantlement queue had dropped to 1,750 warheads because we assumed the annual dismantlement rate had remained around 300. But as the data shows, both the Trump and Biden administrations reduced the number of warheads being dismantled per year.

In 2016, NNSA stated that it “will increase weapons dismantlement by 20 percent starting in FY 2018” and that the “accelerated rate will allow NNSA to complete the dismantlement commitment a year early, before the end of FY 2021.” NNSA reaffirmed in 2018, that all warheads retired prior to 2009 would be dismantled by end-FY 2022.

This pledge appears to have faded from recent documents after the 2018 Nuclear Posture Review was published. Instead, the annual number of warheads dismantled has decreased since FY 2018. Is it still the goal? Some of the warheads that should have been dismantled but are still with us reportedly include the W84 warheads from the ground-launched cruise missiles that were eliminated by the 1987 INF treaty and retired well before 2009.

Many of the warheads in the current dismantlement queue were retired after 2009. At the current rate of 184 warheads dismantled per year, it will take more than a decade to dismantle the current backlog. Once the excess W76s and old gravity bombs enter the queue, it will take even longer.

In Context

We commend the Biden administration for reversing the Trump administration’s shortsighted and counterproductive nuclear secrecy and restore transparency to the US nuclear weapons stockpile. This decision is a heavy lifting at a time when so-called Great Power Competition is overtaking defense and arms control analysis. The Federation of American Scientists has for years advocated for increased transparency of nuclear arsenals and have worked to provide that through our estimates of nuclear weapons arsenals.

Although the recent reductions shown in stockpile and dismantlement data are modest, to put it mildly, we believe declassification is the right decision because making the record public will help US diplomats make the case that the United States is continuing its efforts to reduce nuclear arsenals and increase nuclear transparency. This is especially important in the context of the upcoming January 2022 Review Conference for the Treaty on the Non-Proliferation of Nuclear Weapons. Dissatisfaction with the lackluster disarmament progress – and a belief that the nuclear-armed states are walking back decades of arms control progress with their excessive nuclear modernization programs and dangerous changes to operations and strategy – have fueled support for the Treaty on the Prohibition of Nuclear Weapons (TPNW).

The decision to disclose the stockpile and dismantlement data will also enhance the US credibility when urging other nuclear-armed states to be more transparent about their arsenals. We have no illusions that Russia or China will follow the example in the short term, but keeping the US numbers secret will certainly not help. And over time, the disclosure can help shape discussions and norms about nuclear transparency to shape future decisions. This is also important because the Trump secrecy recently provided cover for the United Kingdom to reduce information about its nuclear forces.

Hardliners will no doubt criticize the Biden administration’s decision to disclose the stockpile and dismantlement data. They will argue that past nuclear transparency has not given the United States any leverage, that nuclear-armed states previously have not followed the example, and it that makes the United States look naive – even irresponsible – in view of Russia and China’s nuclear secrecy and build-up.

On the contrary: without transparency the United States has no case. Past transparency has given the United States leverage to defend its record and promote its policies in international fora, dismiss rumors and exaggerations about its nuclear arsenal, and publicly and privately challenge other nuclear-armed states’ secrecy and promote nuclear transparency. And since the disclosure does not reveal any critical national security information, there is no reason to classify the stockpile and dismantlement data.

Hardliners obviously will have to acknowledge that the data shows that there has been no unilateral US disarmament but only a very modest reduction in recent years. And although there appear to be additional unilateral reductions built into the modernization programs, those are actually programs that have been supported and defended by the hardliners.

Now it is up to the Biden administration’s Nuclear Posture Review to articulate how and to what extent those plans support and strengthen US national security and nonproliferation objectives. Arms control obviously will have to be part of that assessment. The declassified stockpile and dismantlement data will help make the case that additional reductions are both needed and possible.

Background Information:

• US Department of State, Transparency in the U.S. Nuclear Weapons Stockpile, Fact Sheet, October 5, 2021
• “United States Nuclear Forces, 2021,” FAS Nuclear Notebook, Bulletin of the Atomic Scientists, March/April 2021
• “Pentagon Slams Door On Nuclear Weapons Stockpile Transparency,” FAS Strategic Security Blog, April 17, 2019
• Status of World Nuclear Forces, Federation of American Scientists global arsenal page

This article was made possible by generous support from the John D. and Catherine T. MacArthur Foundation, the New Land Foundation, the Prospect Hill Foundation, and the Ploughshares Fund. The statements made and views expressed are solely the responsibility of the authors.

On this day 75 years ago, the world entered the nuclear age. The first ever nuclear detonation – known as the Trinity test – took place in New Mexico on July 16th, 1945. Since then, ten countries built more than 134,000 nuclear weapons. More than 13,400 remain today.

In the decades that followed, nuclear testing contaminated lands, oceans, and people, and triggered a nuclear arms race that continues to this day. The Federation of American Scientists is honored to join our colleagues at the Union of Concerned Scientists and Tularosa Basin Downwinders Consortium in a joint statement with five other U.S. organizations on the humanitarian consequences of nuclear testing, endured by victims in the United States and its Pacific territories, from French nuclear testing in French Polynesia and Algeria, Russian nuclear testing in Kazakhstan, British nuclear testing in Australia, and others.

In addition to these harms, the Trinity test marked the beginning of the global nuclear arms race with its endless cycles of nuclear modernization and competition, which continue to this day. Unlike any other invention, nuclear weapons have the capability to destroy human civilization and much or life on Planet Earth.

The Federation of American Scientists has tracked the rise and fall of global nuclear arsenals for many years. Despite reductions since the Cold War, there are still more than 13,000 nuclear weapons in the world. And we are disappointed to note the emergence of five disturbing trends regarding the current and future state of nuclear weapons:

1. Every nuclear-armed country is currently in the midst of modernizing their nuclear arsenals. Some countries are actually increasing their stockpiles, while others are swapping out their older weapons with newer, more effective ones that will endure almost until the end of the 21st century.
2. Not only are nuclear arsenals either increasing or improving, but it appears that many states are reinvigorating or even expanding the role of nuclear weapons – specifically tactical nuclear weapons – in their military doctrines. State representatives have often claimed that these deployments are actually intended to prevent conflict; however, regardless of how much stake one puts into that sort of statement, it is a fact that many states are now increasingly posturing themselves for nuclear warfighting. This development will make it more difficult to reduce the role of nuclear weapons and pursue significant reductions – and certainly disarmament – in the future.
3. In recent years, we have also seen the decline – and general disinterest – in arms control writ large. Today, bilateral and multilateral arms control agreements have fallen away or are under severe stress, multilateral efforts to engage in good faith arms reductions appear to have completely stagnated, and states often seem more interested in blaming and shaming their prospective arms control partners than actually pursuing measures that would offer a modicum of transparency and predictability in an otherwise unpredictable world.
4. Rather than pursue arms control, it seems that states are more content with pursuing arms competition and even arms races. This is a result of renewed military competition and is fueled by the tremendous influence that weapons contractors and lobbyists have on government decisions; indeed, sometimes nuclear decisions seem to be driven as much – if not more – by corporate interests than by national security concerns.
5. Nuclear-armed states largely do not appear to consider nuclear disarmament to be an urgent global security, humanitarian, or environmental imperative. Instead, most states seem to consider disarmament as a type of chore mandated by the Non-Proliferation Treaty – and not one that they are seriously interested in completing in the foreseeable future. It is increasingly rare to hear any officials from nuclear weapon states express a coherent rationale for pursuing disarmament other than as a result of the obligation to do so under the Non-Proliferation Treaty. Moreover, they seem increasingly focused on shifting the disarmament responsibility onto the non-nuclear states by arguing they first must create the security conditions that will make nuclear disarmament possible.

Although the Trinity test took place 75 years ago, its destructive legacy continues to this day. And despite these harms, some politicians are even trying to return to an era of live nuclear testing. Resuming nuclear explosive testing would be taking a monumental step backward and would open the floodgates for worldwide resumption of nuclear testing and development of new nuclear weapons. Instead, on this 75th anniversary, we must look forward, try our best to reverse these worrying trends, responsibly reduce the arsenals and the role that nuclear weapons serve, and work towards a world eventually free from nuclear weapons.

The Federation of American Scientists is honored to provide the world with the best non-classified estimates of the nuclear weapons arsenals. We are grateful for the financial support from the New Land Foundation, MacArthur Foundation, Ploughshares Fund, and the Prospect Hill Foundation to do this work. To explore this vast data, developed over many decades, start here: https://fas.org/issues/nuclear-weapons/status-world-nuclear-forces/

Amidst a deepening rift between the United States and Russia about the role of non-strategic nuclear weapons, Russia has begun to upgrade an Air Force nuclear weapons storage site near Tver, some 90 miles (145 kilometers) northeast of Moscow.

Satellite photos show clearing of trees within the site as well as the construction of a new security fence and guard post. The upgrade, which started late-2017 and was completed late last year, was followed by the arrival of what appears to be weapons transport and service trucks earlier this year (see image below).

The Tver site includes two nuclear weapons bunkers as well as service and security buildings. The new security fence and gate added within the site separates the bunker area from the service area. The site is near the Migalovo Air Base, which is not thought to be housing nuclear strike aircraft but might serve a nuclear weapons transport function. If so, it could potentially be responsible for the distribution of nuclear warheads to tactical air bases in north-western Russia in a crisis.

It is impossible to determine from the satellite images if the Tver site stores nuclear weapons at this time, but it is clearly active with considerable personnel and activities indicating weapons might be present. Alternatively, Tver could serve as an Air Force storage site in a crisis. Tver is one of several dozen nuclear weapons storage sites operated by the Russian ministry of defense and military services (see here and here.

There are also important upgrades underway at the Mozhaysk-10 storage site about 70 miles (114 kilometers) west of Moscow, including addition of new support facilities as well clearing of a previously tree-covered weapons storage igloo. Mozhaysk-10 is one of a dozen national-level nuclear weapons storage site and includes six underground igloos and appears to be expanding (see below). Mozhaysk-10 might be used to store both strategic and tactical nuclear weapons.

The upgrades at the Tver and Mozhaysk-10 sites follow an ongoing upgrade to a nuclear weapons storage site in Kaliningrad that began in 2016 and appears intended to support nuclear-capable forces in the isolated enclave.

Russia is estimated to possess approximately 6,500 nuclear warheads, of which an estimated 4,330 are thought to be available for use by the military. We estimate that Russia has about 1,830 nuclear warheads assigned to non-strategic forces; the Pentagon says the number is “up to 2,000” warheads. The US Defense Intelligence Agency (DIA) recently said it expects to see “a significant projected increase in the number of Russia’s non-strategic nuclear weapons” over the next decade, although some past DIA growth projections have turned out to exaggerated.

In response, the United States has begun to increase the upgrade of its non-strategic nuclear weapons beyond the already-planned B61-12 guided gravity bomb for stealthy F-35 fighter-bombers. New weapons with “tactical” missions include the W76-2 low-yield warhead on the Trident II D5LE SLBM and a new nuclear sea-launched cruise missile. And NATO has been upgrading US nuclear weapons storage sites in Europe.

Russia and the United States refuse to disclose how many tactical nuclear weapons they have or where they are stored, and none of these weapons are limited by arms control agreements.

We will further describe these developments, and much more, in our upcoming Nuclear Notebook on tactical nuclear weapons scheduled for publication in the Bulletin of the Atomic Scientists in September 2019.

Additional information:

• Russian nuclear forces, 2019
• Status of World Nuclear Forces, 2019

This publication was made possible by generous contributions from the Carnegie Corporation of New York, the John D. and Catherine T. MacArthur Foundation, the New Land Foundation, the Ploughshares Fund, and the Prospect Hill Foundation. The statements made and views expressed are solely the responsibility of the authors.