Nov. 4, 2013—It 
wouldn’t serve US nuclear deterrence—or nonproliferation—goals to modernize the B83 nuclear gravity bomb in place of the B61, senior Defense Department and Energy Department officials told lawmakers last week.
The megaton-class B83 is a “relic of the Cold War,” Madelyn Creedon, assistant secretary of defense for global strategic affairs, told the House Armed Services Committee’s strategic forces panel on Oct. 29. “We need the ’61” for maintaining a credible, forward-deployed tactical nuclear weapon for NATO, and also for extending the US nuclear umbrella to protect allies in Asia, she said.
“The B61 is the best of the choices to go forward,” said Gen. Robert Kehler, head of US Strategic Command, at the same hearing.
They were responding to questioning from Rep. John Garamendi (D-Calif.), who argued it might make sense to invest in keeping the comparatively newer B83 viable instead of the B61, one of the oldest nuclear weapons in the US stockpile. Garamendi was concerned about the estimated cost—more than $10 billion—of the Obama Administration’s planned B61-12 Life Extension Program.
He also questioned the need for maintaining tactical nuclear weapons in Europe.
“If the B83 is good with some repairs over the next decade or more, why do we need the B61?” he asked.
Kehler answered that the B61 is currently the only nuclear bomb “that can arm both the B-2 bomber and dual-capable fighter aircraft deployed by the US and NATO in Europe” as part of the alliance’s nuclear mission. Further, the B61 is the candidate nuclear weapon for the F-35 strike fighter and the future US bomber, he said.
Kehler said the B83 could arm the B-2. However, “the B83 is not currently compatible with NATO aircraft, nor with [US] fighters,” said Donald Cook, the National Nuclear Security Administration’s deputy administrator for defense programs.
The B61-12 LEP would refresh components of the 1960s-vintage B61 and replace the different bomb variants with the single B61-12 configuration.
Completing the B61-12 LEP would enable the United States to retire the B83, the last megaton-class gravity bomb in the US inventory, said Cook. This would make the B61-12 the only nuclear gravity bomb in the US inventory. That’s part of the Obama Administration’s broader nuclear modernization strategy—reducing to fewer nuclear warheads, yet ones that are safer, more reliable, and more secure.
Cook said maintaining the B83 inventory over the long term, including tasks like integrating the bomb on additional aircraft types in lieu of the updated B61, “would be considerably more expensive” than the B61-12 LEP.
The B83 entered service in 1983.
Another argument against the B83 is that it is not as flexible as the B61 in terms of matching various explosive yields to targets, said Kehler. “We’re trying to pursue weapons that actually are reducing in yield because we’re concerned about maintaining weapons that would have less collateral effect if the President ever had to use them,” he said.
A refreshed B61 inventory would enable the United States to maintain a credible extended deterrent to protect its NATO partners and allies in Asia, said Creedon. “In the absence of that reliable extended deterrence, there is a real concern that some of those allies who have the ability to develop their own nuclear weapons would in fact do so,” she said.
NATO allies “have reaffirmed the need” for a forward-deployed tactical nuclear presence for as long as the alliance retains a nuclear mission, said Creedon. While the B61-12 is acceptable, “the idea of introducing a megaton warhead into Europe is almost inconceivable to me at this point,” she said, referring to the B83.
(For more hearing coverage, see Meeting Military Requirements.) (Cook’s written testimony) (Creedon’s written statement) (Kehler’s prepared statement) (See also Hommert’s prepared testimony.)