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WASHINGTON -- The U.S. Defense Department's long-awaited Nuclear Posture Review endorses three different approaches to modernizing aging warheads, but the politically cautious path it attempts to carve could still prove controversial (see GSN, Jan. 19).
(Apr. 7) -
Technicians attach a U.S. W-76 nuclear warhead to a transportation cart. The Obama administration laid out multiple methods of maintaining the U.S. nuclear deterrent in a nuclear weapons strategy review unveiled yesterday (U.S. National Nuclear Security Administration photo).
The yearlong review, mandated by Congress, assessed the nation's nuclear strategy, forces and readiness. Originally expected in December, it was released yesterday during a Pentagon media rollout.
In crafting their findings, senior defense officials said they sought to balance two major objectives that President Barack Obama trumpeted last April in Prague: First, taking "concrete steps" toward the global elimination of nuclear weapons by reducing their role in U.S. strategy, while, second, maintaining a safe, secure and effective arsenal as long as these weapons exist.
Charting a course between those dual goals was tricky -- particularly as the administration seeks to cultivate political support both on the right and left for its nuclear agenda -- and the process spilled over into 2010 as a result.
Major results of the review include altering the nation's "declaratory" posture to clarify the role of the arsenal and when weapons might or might not be used, and announcing that "the United States will not develop new nuclear warheads" (see GSN, April 6).
The review also lays out how the administration will undertake an effort to ensure that the nuclear arsenal remains functional for years to come.
Late last year, all of the Senate's Republican members plus one independent warned the president that they expected to see a robust program to modernize warheads and rebuild the nuclear-weapons design and production infrastructure before they would consider voting to ratify a new U.S.-Russian nuclear arms control agreement (see GSN, Dec. 17, 2009). In February, Obama submitted to Congress a fiscal 2011 budget request that included a 13.4 percent increase in funds for the nuclear complex (see GSN, Feb. 2).
In deciding its game plan for modernizing nuclear warheads, the Obama administration hewed fairly closely to guidelines for "Stockpile Management" that Congress spelled out in fiscal 2010 legislation. A defense authorization report issued last year said any updates must be limited to improving warheads' safety, security and reliability, without adding more explosive power or boosting a weapon's capability against targets.
The challenge has been to find ways to establish confidence that nuclear weapons will continue to function, if necessary, in the absence of explosive testing. The United States has maintained a voluntary moratorium on underground tests since the early 1990s.
Under the new Obama policy, "life-extension programs will use only nuclear components based on previously tested designs, and will not support new military missions or provide for new military capabilities," the posture review states.
The particular approach to warhead overhauls will be determined on a case-by-case basis, as each weapon comes up for periodic overhaul in a "life-extension program," according to the Nuclear Posture Review.
"The full range of LEP approaches will be considered: refurbishment of existing warheads, reuse of nuclear components from different warheads, and replacement of nuclear components," states the posture review report.
Gen. James Cartwright, vice chairman of the Joint Chiefs of Staff, yesterday described refurbishment as the renovation of a warhead in such a way that it would not change its key nuclear components, sometimes called its "physics package."
Under the second method of updating a warhead -- reuse -- engineers might reach into existing reserve stockpiles and cannibalize a component "from one warhead type, [and] match it with another in order to be able to preserve that weapon," said Cartwright, who formerly served as the top combatant commander for nuclear weapons. "That would allow us to take known, tested designs, keep them in the stockpile without having to retest or establish a test program, and allow us to keep the stockpile fresh."
Briefing reporters on some of the review's conclusions, the general described the third option -- replacement -- as "utilizing [warhead] designs not in the stockpile but based on previously tested designs." This method would involve new production of existing blueprints, and -- as in the case of reuse -- could combine parts that were never explosively tested together in the same warhead.
However, the replacement option will not be considered on equal footing, according to the posture review.
"In any decision to proceed [on] warhead LEPs, the United States will give strong preference to options for refurbishment or reuse," the document states. "Replacement of nuclear components would be undertaken only if critical Stockpile Management Program goals could not otherwise be met, and if specifically authorized by the president and approved by Congress."
Most lawmakers have taken a dim view of nuclear-warhead "replacement" options over the past several years, twice rejecting Bush administration requests to fund a "Reliable Replacement Warhead." Under that now-canceled effort, U.S. officials proposed swapping older weapons across the arsenal for new models that could be safer to maintain, pose less risk of unauthorized use and remain functional for the foreseeable future.
Obama has supported RRW cancellation, but his defense secretary, Robert Gates, championed the effort when he served under former President George W. Bush (see GSN, Oct. 29, 2008).
The defense secretary yesterday expressed full support for the Nuclear Posture Review findings, saying warhead "replacement" would be conducted only if "absolutely necessary."
"He still fundamentally believes that it is necessary to modernize our nuclear arsenal to ensure that we have a safe, secure and reliable deterrent," Geoff Morrell, Gates' spokesman, told Global Security Newswire in January. "Whether that's done under a program called RRW or whether that's done under the Stockpile Management Program I think is less of a concern to him than the fact that we need to modernize without developing new capabilities."
The new review leaves open the option of nuclear component replacement, albeit as a last resort. That has rankled several on the president's left flank, who want to see replacement renounced altogether.
"Efforts to pursue newly designed warheads are technically unnecessary and would undercut our efforts to convince other nations to forgo nuclear weapons or refrain from developing new and more advanced types of nuclear warheads," stated a February letter to Obama from 13 leading arms control and nonproliferation advocates.
In November, a panel of top scientists told the U.S. government that traditional refurbishment methods have worked well to date and should be sufficient in the coming years (see GSN, Nov. 20, 2009).
"Lifetimes of today's nuclear warheads could be extended for decades, with no anticipated loss of confidence, by using approaches similar to those employed" in maintaining the stockpile to date, according to JASON, a panel of senior scientific and technical experts frequently consulted by the U.S. government.
This week, though, Obama is hearing criticism from the right, which is already frustrated by his decision to somewhat set aside the replacement option that they regard as a potentially crucial tool for maintaining a reliable stockpile. The political pushback comes shortly after the heads of all three nuclear weapon design laboratories disputed some of the JASON findings (see GSN, March 29).
"We expect the administration will not take any option off the table to ensure the military and the directors of the national laboratories are able to maintain the safety, security and reliability of the current stockpile," Senators John McCain and Jon Kyl, both Arizona Republicans, said in a statement released yesterday. "We will evaluate this carefully in the coming weeks, including when we see the modernization plan required by law at the time the START follow-on treaty is submitted to the Senate."
Even if policy or political differences over warhead-replacement options were set aside, new concerns appear to be cropping up over component "reuse," one of the other two potential approaches to modernization. Some leading scientists are concerned that combining components from different warheads that were never explosively tested with one another, prior to the moratorium, could lead to decreased confidence and malfunctions in U.S. nuclear arms.
"You have to be careful mixing and matching tested components that were never tested together," said Roger Logan, who formerly led directed stockpile work at the Lawrence Livermore National Laboratory in California.
He cited a nuclear physicist with decades of experience stating in 2004, when a version of component reuse was proposed in the RRW effort: "Whenever we've tried that, it's always been the thing we didn't think of that bit us."
"The idea is not adding more risk to the arsenal," Thomas D'Agostino, head of the National Nuclear Security Administration, told GSN in a brief interview yesterday at the Pentagon. "The idea right now is to take advantage of components that we've already made, take advantage of components that we've already tested, and study whether or not they can be used to advance safety, security and reliability."
His agency is a semiautonomous arm of the Energy Department that maintains the U.S. nuclear stockpile. In the past, the nuclear complex has also been responsible for designing and producing new warheads.
While D'Agostino warned against "point blank" rejection of reuse options that suggest "you can't do it at all," Logan told GSN that he does not "know of any experts in the reliability community who would favor or even accept these mix-and-match 'reuse' warheads, or the way [the national laboratories] plan to 'certify their reliability.'"
Asked how confidence could be established in reuse warheads without a resumption in explosive testing, D'Agostino said past testing data combined with new analyses should provide a strong foundation for certifying such repackaged weapon-component combinations.
"We have a lot of testing that we have done already that has never been deployed in the stockpile," he said. "We're going to use ... modeling and simulation that we've done, we're going to do a lot of subcritical testing, and things like that."
Logan took issue with the idea that validation of the stockpile could be accomplished in the absence of data from explosive tests that assessed components as they operated together in the same warhead, saying this newly proposed approach would not meet scientific standards. He supports refurbishment of existing designs as the only method of maintaining confidence in the arsenal into the future.
"Refurbishment may be less 'sexy' and less 'profitable' for the nuclear labs, but many of the nuclear complex engineers, scientists and production people find it quite rewarding and a challenge to be met," Logan told GSN yesterday in an e-mailed response to questions. "For those who find the task boring, I suggest they find a fun hobby at their own expense, and one that does not turn our nuclear deterrent into 'junkyard RRWs.'"
He used the term to describe an earlier-contemplated approach for building the Reliable Replacement Warhead, in which old parts from various warheads could be pieced together in new ways.
Morrell said the defense secretary is in sync with the White House in developing an approach to modernization that could attract bipartisan support.
"Gates is in no way holding out hopes of resuscitating RRW," Morrell said. "He is very much trying to work to figure out a way in which to maintain a safe, secure and reliable deterrent with the new administration."
D'Agostino acknowledged that warhead modernization could slightly boost risks of weapon malfunction, but said the end objective makes such a chance worth taking.
"As you step down the track, you will obviously take on a little bit more risk," the NNSA administrator said. "But that risk has to be counteroffered with the safety and security benefits that you get."