Nuclear Weapons

End of the B53 Era; Continuation of the Spin Era

10.25.11 | 5 min read | Text by Katie Colten

Hans Kristensen with B53 Bomb

By Katie Colten and Hans Kristensen

[Modifed] Today, one of the largest weapons in the United States nuclear weapons arsenal, the B53, will be dismantled at the Pantex Plant in Amarillo, Texas. Developed during the Cold War and deployed in 1962, this bomb weighs as much as a minivan and has an explosive yield of nine megatons, equivalent to 750 Hiroshima bombs.

Retired from the arsenal in 1997, the dismantlement of the B53 marks the end of the era of large, multi-megaton bombs, a hallmark of the Cold War. The largest-yield warhead in the U.S. stockpile today is the B83 bomb, which has a maximum yield of 1.2 Megatons.

Administration officials have been busy spinning the dismantlement as proof of the administration’s commitment to nuclear disarmament and as vindication of its plan to spend billions of extra dollars to modernize the nuclear weapons production complex.

In a statement published on the National Nuclear Security Administration (NNSA) web site, Daniel Poneman, the deputy secretary of energy, said that the B53 dismantlement “is a major accomplishment that has made the world safer,” and that “safely [sic] and securely dismantling surplus weapons is a critical step along the road to achieving President Obama’s vision of a world without nuclear weapons.”

“The elimination of the B53 is a significant milestone in our efforts to reduce the number of nuclear weapons and implement President Obama’s nuclear security agenda,” said Thomas D’Agostino, head of NNSA. “Today, we’re moving beyond the Cold War nuclear weapons complex that built it and toward a 21st century Nuclear Security Enterprise.”

If the B53 dismantlement indeed “is a major accomplishment that has made the world safer” and “a critical step along the road to achieving President Obama’s vision of a world without nuclear weapons,” as Boneman says, one might ask why it took 13 years to dismantle the weapon after it was retired in 1997? One reason is that dismantlement is not the priority at the Pantex Plant, which is busy with full-scale production of the W76-1 warhead for U.S. and British sea-launched ballistic missiles, as well as surveillance and repair of the warheads in the “enduring stockpile.”

Warhead Dismantlements

We certainly congratulate the administration on finally dismantling the old B53, but one should not over-spin the achievement. The B53 dismantlement involves less than 50 warheads; the U.S. has approximately 8,500 intact warheads (counting those in the stockpile and dismantlement queue). And warhead dismantling under the Obama administration continues to follow the low rate standard set by the Bush administration. The current dismantlement rate is secret (though past history has been declassified), but very low (only 300-400 warheads per year, according to my estimate) compared with the rate during the 1990s when more than 1,000 warheads were dismantled each year. And it’s not as if there is a lack of retired warheads waiting to be dismantled: more than 3,000 (according to my estimate; the official number is also secret). At the current rate, the backlog of warheads retired through 2009 will not be dismantled until 2022. Additional warheads retired after 2009 will push the completion date further into the future.

Dismantlement performance is an important way to demonstrate U.S. commitment to non-proliferation and disarmament, but the low rate and the secrecy undermine that important effort. And so does the spin. When D’Agostino said in May 2009 that the dismantlement rate had risen more than 150 percent since 2006, he didn’t say that it would drop by half in 2009. Nor did NNSA announce the reduction. Rather than cherry-picking the good news and hiding the bad behind secrecy, the administration should disclose the real numbers and let them speak for themselves.

Warhead Safety

We also agree that it is good to get rid of an unsafe weapon. But since NNSA points to the importance of safety, one should not gloss over the fact that consecutive administrations allowed the B53 to remain in the stockpile even though they knew full well that it was unsafe. The Reagan administration retired the B53 but then decided in 1987 to return the weapon to the stockpile to stand alert against Soviet underground facilities. After a review in 1991 found the B53 to be unsafe, DOE “strongly recommended” to DOD in 1993 that the weapon be retired at the “earliest possible date.” Yet the B53 war allowed to remain in the stockpile for another four years until 1997 when its mission was taken over by the new B61-11 nuclear earth penetrator.

The B53 is not the only case of safety being overruled by targeting requirements. The W62 warhead, the last of which was dismantled in August 2010, was deployed on the Minuteman III ICBMs through 2009, even though the warhead had a lower safety rating than the B53 (D versus C-, according to a 1991 Lawrence Livermore National Laboratory study). The W62 safety exemption is all the more striking given that the ICBMs that carried the warhead were on high alert, something that ended for the B53 in 1991.

Even though it was found to be more unsafe than the B53 bomb, the W62 warhead (seen here at Warren Air Force Base in 2009) was allowed to continue to arm Minuteman III ICBMs on alert until 2009.

Nuclear Funding

As for the B53 dismantlement being used to justify funding the modernization of the nuclear weapons complex, that claim is certainly a stretch given the dismantlement was done using the “old” complex; the modernized complex is not scheduled to come online until the mid-2020s, at which point the current backlog of retired nuclear warheads will be gone. NNSA’s nuclear weapons budget has already been increased by 10 percent over the Bush administration, and the latest Stockpile Stewardship and Management Plan shows that the administration plans another 10 percent increase. That funding level is incompatible with current fiscal realities, and no amount of B53 spin can change that fact.

News Clips:

Oct 26: USA Today, “U.S.-made ‘monster’ nuclear warhead B53 dismantled
Oct 25: Associated Press“US’s most powerful nuclear bomb being dismantled”
Oct 25: National Public Radio – All Things Considered“Cold War Bomb to be Dismantled”
Oct 25: Agence France-Presse“U.S. Dismantles Last Big Cold War Nuclear Bomb”
Oct 25: Wired UK“Last Nuclear ‘Monster Weapon’ Gets Dismantled”
Oct 25: Daily Mail (UK)“Dismantling the mega-nuke: America begins to take apart B53 that was 600 times more powerful than bomb that flattened Hiroshima”
Oct 25: Gawker“Goodnight Sweet ‘Monster Weapon'”

More Information:

October 2010: FAS Strategic Security Blog“Scrapping the Unsafe Nuke”
2005:, “Reagan Administration Decision to Retain the B53
April 2005:, “The Birth of a Nuclear Bomb: B61-11
December 1991: Lawrence Livermore National Laboratory“Assessment of the Safety of U.S. Nuclear Weapons and Related Nuclear Test Requirements: A Post-Bush Initiative Update”

This publication was made possible by a grant from Carnegie Corporation of New York and Ploughshares Fund. The statements made and views expressed are solely the responsibility of the author.