Pakistan Calls Nuke Program Security 'Foolproof'

In response, Kidwai warned that "words mean nothing. [Mehsud] could change his mind tomorrow. He has a capability. We are ready for him."

But the government has some doubters. Pervez Hoodbhoy, the chairman of the physics department at Islamabad's Quaid-e-Azam University, says the program's safeguards are not foolproof.

"They may well have taken good care of certain things like electronic locks and safety devices, and they probably do keep the weapons disassembled. But they cannot know for sure that, in the times ahead, the custodians of the weapons will always be responsible to the government," he told ABC News.

"Following U.S. practices, they now do psychological screening of personnel," he said. "But I would find it hard to believe that such tests can spot the difference between those men who are merely strong in faith versus those who believe, in addition, that nuclear weapons are needed for defending the faith."

Before ElBaradei made his comments, which he later backed away from, Sen. Hillary Clinton suggested that Pakistan should be willing to give up control over its own nuclear program.

"I would try to get [President Pervez] Musharraf to share the security responsibility of the nuclear weapons with a delegation from the United States and, perhaps, Great Britain, so that there is some fail-safe," she said during a debate last month.

The Pakistani government has responded angrily to such proposals, and Kidwai said that Pakistan would "never" give up control over its nuclear facilities, saying there was "no conceivable scenario, political or violent, in which Pakistan will fall to the extremist."

Pakistan's weapons, he said, are "not on hair trigger alert," and are safer because of that than they would otherwise be, though he did mention that they could be ready in "no time."

For nearly two hours inside a barracks in Rawalpindi, the headquarters of Pakistan's military, Kidwai used a PowerPoint presentation to describe exactly how the nuclear program is run and safeguarded.