When a collection of nuclear arms control experts visited the Pentagon in July for a briefing on the president's nuclear posture review, they were escorted to the secure conference room by an employee for a government contractor whose company, SAIC, is staffing the review. And when Bradley A. Roberts, the Pentagon official in charge of the review, suggested at the meeting that a report he authored arguing for strong nuclear deterrence be used as a jumping off a point, the words rippled throughout Washington's arms control community: the Pentagon, it seemed, was about to take control the Nuclear Posture Review once more.

Tensions between hawks, doves and deterrencers have proliferated for decades, but in the administration of a president who has vowed to take concrete measures to change U.S. nuclear strategy and reduce American nuclear arsenals, they are especially acute. The White House's message to its allies has been low-key: trust Obama, they say, to make the right decisions in the end. But there are divisions at the top. Vice President Biden is fighting an effort, led by Secretary of Defense Robert Gates, to modernize nuclear weapons, fearing that in doing so, the weapons' capabilities will be enhanced. The National Security Council has taken a largely passive role in interagency discussions -- so far. Even at the State Department, the talk is of compromise and vote-trading, with elements of the strategy review being used as bait to secure 67 vote majorities on major arms reduction treaties.
According to senior administration officials, the president plans to take a more active role in shaping the NPR debate in the fall but said that he trusts the team he has put in place to make sure the document reflects his views. It is due to Congress in early February, which means that the major decisions must be made by the end of this year. Some administration officials say that a clash between the State Department and the Department of Defense is inevitable, and that presidential leadership will be needed to bridge the philosophical chasms that divide the two bureaucracies. Officials said that Obama will use a speech before the U.N. Security Council to make concrete progress toward his Prague vision, but they declined to offer specifics.
 
During the presidential campaign, Obama said he endorsed the call by leading lights of foreign policy, George Schultz, Henry Kissinger, William Perry and Sam Nunn, to reduce America's nuclear arsenal to zero.

In April, Obama delivered what some of his advisers billed as the most ambitious speech of his presidency: to an audience in Prague, the city at the crossroads of Europe, he spoke of his belief that a nuclear-free world was not only possible, but that he would lead a worldwide effort to make it a reality
 
"Just as we stood for freedom in the 20th century, we must stand together for the right of people everywhere to live free from fear in the 21st. And as a nuclear power -- as the only nuclear power to have used a nuclear weapon -- the United States has a moral responsibility to act. We cannot succeed in this endeavor alone, but we can lead it," he said. "So today, I state clearly and with conviction America's commitment to seek the peace and security of a world without nuclear weapons."
 
Then, for the community of non-proliferators, came the clincher: "To put an end to Cold War thinking, we will reduce the role of nuclear weapons in our national security strategy and urge others to do the same."
 
The president was engaging in a bit of dog whistling to the arms control community. His words suggested a break with the current nuclear strategy of the United States, first set in 1994 by an aggressive Department of Defense and a passive Clinton administration and then ratified and expanded by the Bush administration in 2002. The 2010 Nuclear Posture Review, a comprehensive, congressionally mandated report about America's nuclear strategy, will contain more than just words: it will be an expression of values and of intent.

In Prague, Obama didn't exactly change policy:  so long as nuclear weapons existed, the U.S. would maintain an arsenal "to deter any adversary, and guarantee that defense to our allies." According to administration officials, the president's classified guidance to his NPR team included an instruction to preserve the U.S.'s general deterrent capacity. The Pentagon has interpreted that instruction to mean that the president wants his nuclear weapons stockpile to be in working order.
 
"A valid concern is that if we produce a new weapon or type of weapon, it makes it a lot harder for us to go around the world telling countries like North Korea, Pakistan and Israel  not to produce a new type of weapon. On the other hand, if we are going to do what the president has said we're going to do in Prague and reduce the stockpile, we need to have the utmost confidence in the stockpile," an administration official directly involved in the review said. "A smaller arsenal means a smaller margin for error."

Based on the president's public silence since Prague and the sense that Pentagon prerogatives are paramount, the broad center-left anti-proliferation community, which had expected so much from President Obama, is beginning to worry. 

Joe Cirincione, a veteran arms control expert who is president of the Ploughshares Fund, tweeted his dismay after leaving a closed-door Pentagon meeting in July. The process, he implied, had been hijacked by the bureaucratic imperatives of the U.S. nuclear forces command, STRATCOM, and by conventional thinking. Daryl Kimball, president of the Arms Control Association of Washington, urged the president and his Cabinet to step up -- and quickly. He was a lonely voice at the first annual Strategic Deterrence Symposium in late July. 

"From the pro-disarmament standpoint, the real question is: will this bureaucracy deliver to him the options that he expects, or will they hand in some unpalatable options that aren't consistent with Prague," Kimball said.

As with many other national security realms, Obama's kitchen cabinet on nuclear issues is diverse.
 
There are very outright hawks, even at the Pentagon, where most military planners and probably a strong majority of flag officers believe that the existence of America's nuclear arsenal is simply the tax that America has to pay for its role in the world. Gates worries about the strategic implications of aging nuclear weapon stockpiles. Secretary of State Hillary Clinton spelled out a vigorous vision of nuclear deterrence in the presidential campaign and is positioned to the right of many of her advisers and deputies. 
 
At the National Security Council, Gary Samore, a veteran arms control negotiator, leads a 10-person team that coordinates policy on everything from the NPR to arms control reduction agreements to weapons proliferation. Robert Einhorn, a longtime Washington hand, is advising Clinton on non-proliferation matters.
 
Defense Department officials have a range of views. The point person on the NPR is Roberts, the Deputy Assistant Secretary of Defense for nuclear matters. Roberts's willingness to push the Pentagon bureaucracy toward a new nuclear posture is questioned by some of his counterparts at the State Department, who point to his service on a federal commission that this May urged the U.S. to maintain a strong and modern nuclear force and to enshrine the concept of expansive deterrence in its strategy. The chief defense policy official, undersecretary Michelle Flournoy, has yet to express her position in public.
 
At State, the newly confirmed undersecretary for arms control, former Rep. Ellen Tauscher, has the Obama Prague vision in her duty charge. Tauscher, a hard-headed pragmatist, led the fight in the House to kill funding for a new generation of warheads and has talked privately about changing the metaphors that guide thinking about policy.
  
The flash point for the internal disputes so far has to do with the current stockpile of nuclear warheads. Earlier this year, the White House overruled Gates and told the Department of Energy to zero out money in his budget for a "Reliable Replacement Warhead" (RRW) program. But Gates has argued internally that existing weapons are too outdated to be a successful deterrent, even with a more limited mission, and has persuaded some contemporizers, including, reportedly, Secretary of State Hillary Clinton, that the National Nuclear Security Administration, which maintains the nuclear weapons arsenal, deserves more funding. The internal disagreements were first reported by Global Security Newswire, an Atlantic Media publication.
 
Vice President Biden, an opponent of an RRW program in the Senate, disagrees with Gates, officials say. As a member of the Senate, Biden associated the RRW with expansionist foreign policies pursued by President Bush, which used its NPR to advocate for a new generation of bunker-busting tactical nukes. And Biden grew even more skeptical when independent studies regularly undercut the Pentagon's claims about the RRW's potential. Biden may well be the senior official who brokers a compromise. Biden's chief nuclear policy adviser, Jon Wolfsthal, is firmly in the strategy-change camp. Biden's main ally in the administration is Susan Rice, a long-time Obama adviser and now the U.S. Ambassador to the United Nations. Rice helped Obama write his Prague speech.
 
If there are new warheads to be built -- the current stockpile hasn't been tested since 1992 and a modernization program might be too expensive and risky -- the key question will be one of capabilities: do the new weapons add tactical value to the forces, or are they simply technologically sound placeholders for a stockpile that's only to be used as a deterrent? To opponents of the RRW, the answer is clear: no way would the Defense Department not find a way to make sure that the new generation of weapons is more technologically advanced than the existing one. To folks at the 8 nuclear weapons sites around the country, it's kind of a joke to compare weapons modernization to a new warhead...they're working in buildings designed for the Manhattan project and maintaining warheads built 20 years ago that weren't designed to last for that long.
 
On September 24, Obama will address the United Nations and chair a meeting of the Security Council on proliferation. Some in the arms control community hope that Obama will use the speech to declare that the United States would never use a nuclear weapon to attack a country that doesn't possess the capability. Doing so would immediately shift the tone and tenor of the NPR, which the administration officially must submit early next year.

Congress is key, here: in order to secure 67 votes on the START II follow-on treaty with Russia (especially if it calls for significant arms reductions) and the Comprehensive Nuclear Test Ban treaty, which Obama has urged Congress to ratify, the president probably needs to convince senators like John McCain and Jon Kyl that the current arsenal can meet current strategy, whatever it may be. And that means compromise -- and modernization.

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