America’s Nuclear Weapons Arsenal 2024: Annual Overview Released by the Federation of American Scientists
FAS researchers, in partnership with the Bulletin of Atomic Scientists, release this seminal account each year in the “Nuclear Notebook”
Washington, D.C. – May 7, 2024 – Nuclear experts at the Federation of American Scientists (FAS) today released “Nuclear Notebook: United States Nuclear Weapons 2024,” an annual overview of the current status and trends of the U.S. nuclear weapons arsenal. The FAS Nuclear Notebook is widely considered the most accurate public source for information on global nuclear arsenals for all nine nuclear-armed states.
This year’s report, produced in partnership with the Bulletin of Atomic Scientists and available in full here, shows the following nuclear trends as Americans enter a presidential election year:
- Across-the-board nuclear modernization is well underway;
- The modernization plan initially envisioned life-extending existing warheads for existing force structure but is evolving into a more ambitious program of new warhead designs and additional weapon types;
- Significant parts of the modernization program are challenged by rising costs and delays (for example, the Sentinel ICBM program is projected to cost 37% more than just four years ago);
- Deployment of new B61-12 guided nuclear bomb to Europe imminent;
- Strategic competition with Russia and China fuel calls for more nuclear weapons;
- Despite calls for transparency of adversarial arsenals, nuclear secrecy at home has increased.
In this issue of the Nuclear Notebook, FAS estimates that the United States maintains a stockpile of approximately 3,708 warheads—an unchanged estimate from the previous year. The total number of U.S. nuclear warheads are now estimated to include 1,770 deployed warheads, 1,938 reserved for operational forces. An additional 1,336 retired warheads are awaiting dismantlement, for a total inventory of approximately 5,044 warheads.
Of the deployed warheads, FAS estimates 400 are on intercontinental ballistic missiles [ICBMs], 970 on submarine-launched ballistic missiles [SLBMs], and 300 are located at bomber bases in the United States and approximately 100 tactical bombs are at European bases.
The United States has embarked on a wide-ranging nuclear modernization program that will ultimately see every nuclear delivery system replaced with newer versions over the coming decades. The total cost of this modernization could reach over $1.7 trillion. Calls to increase the nuclear arsenal would increase cost further and compete with non-nuclear defense needs.
The New START treaty, established in 2010 between the United States and Russia, has proven useful so far in keeping a lid on both countries’ deployed strategic forces. But the treaty expires in February 2026 and a decision to renew or not will be made by the next administration. If it is not followed by a new agreement, both the United States and Russia could potentially increase their deployed nuclear arsenals by uploading several hundred of stored reserve warheads onto their launchers.
FAS Nuclear Experts and Previous Issues of 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 arsenal and their role.
This latest issue on the United State’s nuclear weapons comes after the release of Nuclear Notebook: Russian Nuclear Forces, 2024 on Russia’s nuclear arsenal. More research is located at FAS’s Nuclear Information Project.
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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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