Pakistani Army soldiers guard nuclear-capable missiles at the International Defence Exhibition in Karachi.
When asked last year about the security of Pakistan's nuclear arsenal, Joint Chiefs of Staff chairman Admiral Mike Mullen didn't hesitate: "I'm very comfortable that the nuclear weapons in Pakistan are secure," he said flatly. Asked the same question earlier this month, his answer had changed. "I'm reasonably comfortable," he said, "that the nuclear weapons are secure."
As America's top military officer, Mullen has traveled regularly to Pakistan — twice in just the past two weeks — for talks with his Pakistani counterpart, General Ashfaq Kayani, and others. And like all those who have risen to four-star rank, Mullen chooses his words with extreme care. Replacing "very comfortable" with "reasonably comfortable" is a decidedly discomforting signal of Washington's concern that no matter how well-guarded the nukes may be today, the chaos now enveloping Pakistan doesn't bode well for their status tomorrow or the day after. (See pictures of the recent militant attack on a Pakistani police academy)
The prospect of turmoil in Pakistan sends shivers up the spines of those U.S. officials charged with keeping tabs on foreign nuclear weapons. Pakistan is thought to possess about 100 — the U.S. isn't sure of the total, and may not know where all of them are. Still, if Pakistan collapses, the U.S. military is primed to enter the country and secure as many of those weapons as it can, according to U.S. officials.
The U.S. has been keeping a watchful eye on Pakistan's nukes since it first detonated a series of devices a decade ago. "Pakistan has taken important steps to safeguard its nuclear weapons, although vulnerabilities still exist," Army General Michael Maples, chief of the Defense Intelligence Agency, told the Senate Armed Services Committee last month. Then, he immediately turned to the threat posed by al-Qaeda, which, along with the Taliban, is sowing unrest in Pakistan. "Al-Qaeda continues efforts to acquire chemical, biological, radiological or nuclear materials," he said, "and would not hesitate to use such weapons if the group develops sufficient capabilities."
The concern in Washington is less that al-Qaeda or the Taliban would manage to actually seize Pakistan's nuclear weapons, but instead that increasingly-radicalized younger Pakistanis are finding their way into military and research circles where they may begin to play a growing role in the nation's nuclear-weapons program. Pakistani officials insist their personnel safeguards are stringent, but a sleeper cell could cause big trouble, U.S. officials say.
Nowhere in the world is the gap between would-be terror-martyrs and the nuclear weapons they crave as small as it is in Pakistan. Nor is their much comfort in the fact that Abdul Qadeer Khan, the father of Pakistan's nuclear arsenal who was recently ordered freed from house arrest by the country's supreme court, was the Johnny Appleseed of nuclear proliferation, dispatching the atomic genie to Iran, Libya and North Korea. But U.S. and Pakistani officials insist it is important to separate Pakistan's poor proliferation record with what is, by all accounts, a modern and multilayered system designed to protect its nuclear weapons from falling into the wrong hands.
For starters, according to U.S. and Pakistani officials, there is no way a complete nuclear weapon can be plucked from Islamabad's stockpile, which is protected by about 10,000 of the Pakistani military's most elite troops. The guts of the nuclear warhead are kept separate from the rest of the device, and a nuclear detonation is impossible without both pieces. Additionally, the delivery vehicle — plane or missile — is also segregated from the warhead components.
Over the past decade, Pakistan has created the National Command Authority and the Strategic Plans Division to manage the nuclear infrastructure from day to day, and the U.S. has given Pakistan an estimated $100 million since 9/11 to bolster the security of its arsenal. While much of that has been spent on bringing Pakistani nuclear personnel to the U.S. for training, it has also been spent on hardware, including various surveillance and security systems.
Then, there's the touchy area of "permissive action links" — the electronic "locks" on nuclear weapons that must be "opened" for a nuclear detonation to take place. Washington doesn't share its own PALs with other countries for fear of losing control of the technology and surrendering key elements about U.S. weapons design (although installing PALs on another country's nukes — with a secret "kill" capability that could remotely render the weapons impotent — has always been a tempting option). "Permissive action links are custom-made devices based on the design and configuration of the weapons," former senior Pakistani nuclear official Naeem Salik told TIME 16 months ago. Until late 2005, he had served as director of arms control and disarmament affairs at Pakistan's National Command Authority, created in 1999 as the command and control center for Pakistan's nuclear weapons. "Unless one is willing to share the technical configuration of the weapon, a permissive action link cannot be developed. We did not share these secrets, so we never asked for the permissive action links — our people have developed our own."
That may all be well and good, Mullen seemed to suggest to NBC during a Wednesday interview in Afghanistan, just before he headed across the border to Islamabad. But, he cautioned, it may not be good enough, given the turmoil racking Pakistan. "My long-term worry," Mullen said, "is that descent — should it continue — gives us the worst possible outcome there."