Calculating the Risks in Pakistan

A concern of some proliferation experts is that in an internal breakup, a contending faction might seek to grab some of the nuclear warheads, not necessarily to use them but to wield them as a symbol of authority. "I think there is a lot of concern about this, and the less stable the government and the society become, the greater the concern," said a senior U.S. intelligence officer whose agency wouldn't permit him to speak for attribution. That said, he added in an interview, the sense inside the intelligence community currently is that the threat isn't dire. Also, he said, "The good news is that Pakistan . . . takes this very, very seriously."

But what if the government of Pakistan can't ensure the security of the nukes? "Then I would agree there are no good answers," he said. So far, Pakistan's internal crisis hasn't become widely violent, he noted. "I think if things get violent, if the government loses control, then one considers the risks in a more active way."

The war games conducted by the U.S. government and by other experts offer a recurring conclusion: Retaining the cooperation of the Pakistani government, especially its military, is crucial. "Our best bet to secure Pakistan's nuclear forces would be in a cooperative mode with the Pakistani military, not an adversarial one," said Scott Sagan, a Stanford University expert in counterproliferation.

Sagan argued that mere contemplation of a U.S. intervention might actually increase the chances of terrorists acquiring a nuclear warhead. He said that in a crisis, the Pakistani government might begin to move its nuclear weapons from secure but known sites to more secret but less-secure locations. "If Pakistan fears they may be attacked," he said, then the Pakistani military has an incentive "to take them out of the bunkers and put them out in the countryside."

In such locations, Sagan concluded, the weapons would be more vulnerable to capture by bad actors. "It ironically increases the likelihood of terrorist seizure," said Sagan, who in the past has advised the Pentagon on nuclear strategy. He noted that Pakistan moved some of its arsenal in September 2001, when it feared it might be attacked.

But Khan, the retired Pakistani brigadier, said that Sagan's fears are misplaced. The weapons "are in secure bunkers, with multiple levels of security, and active and passive measures" to mask their presence, he said. And while he conceded that the Pakistani government moved some nuclear weapons in 2001, he said the shifts made the arsenal more secure, not less.

The senior U.S. intelligence officer also disagreed with Sagan's view that Pakistani moves might make its arsenal more vulnerable. "I think that implies they haven't thought thoroughly about this," he said. "They've looked at it from all sorts of angles. . . . They think they're doing everything they can."

The bottom line, said Oakley, the veteran diplomat, is that "the only way you can safeguard them is to work very, very closely with the Pakistani army." To attack that army, he said, would erode the one institution that is keeping the weapons under control. "If you want nukes to get loose," he said, "that's the way to do it."