Nothing worries the world more than the combination of Pakistan's nuclear arsenal, its political instability and its past record of proliferation.
More than the assassination of Benazir Bhutto, however, it has been recent evidence of jihadi infiltration of the Pakistani military that have resurrected fears of an "atomic Taliban" scenario.
There is a clear divide over how to handle Pakistan's nuclear problem. Non-proliferation and counter-terrorism experts argue nothing is more important than securing Pakistan's arsenal.
This means putting one's eggs in the military basket and backing dictators like Pervez Musharraf to the hilt. Former head of arms control in the US State Department, John Bolton, once said the general "is the best bet to secure the nuclear arsenal".
Others argue nuclear safety is best assured by political stability. And stability means a democratic government.
"Pakistan's arsenal is worth worrying about. But that doesn't necessarily lead to the conclusion that you have to build policy around a military strongman. Moving toward political legitimacy is a strong protection," says Teresita Schaffer, South Asia expert at the Center for Strategic and International Studies.
This thesis has been supported by a recent study of AQ Khan's nuclear black market operations by the International Institute for Strategic Studies and a book,
The Nuclear Jihadist
, by Douglas Frantz and Catherine Collins. Both conclude the fragmented nature of Pakistan's polity allowed Khan to sell nuclear secrets freely. "The diffusion of domestic political power among the troika of the President, Prime Minister and the Army Chief, obscured the command and control authority over the covert nuclear weapons programme," says the IISS report.
The Pakistani military alternate between warning of a Taliban take-over and assuring the world that its estimated 50 nuclear warheads are safe.
Raising the latter fear buttresses support for the military in Washington. Says Frederic Grare, Pakistan analyst at Carnegie Endowment: "The military always use the nuclear bogey as leverage against the US."
On the other hand, several reports have said the US maintains contingency plans for either bombing or capturing Pakistan's half-a-dozen nuclear installations in case the country looks like it is losing control of its arsenal. References to military cooperation with India in handling "third countries" losing control of their nuclear bombs in the Pentagon's Quadrennial Defence Review indicate New Delhi would have a role in such a contingency plan.
Says Stephen Cohen of the Brookings Institute and author of
The Idea of Pakistan
: "Pakistanis fear a US or Indian attack on their arsenal."
While most analysts say Pakistan's arsenal is in no specific danger from the present turmoil, the larger concern is that the lack of a legitimate government feeds into a broader political crisis in Pakistan — one that is infecting the professionalism of the military as well.
The Pakistani military's operations in the Northwest Frontier Province against Islamic insurgents have seen record levels of court martials and desertions.
Former RAW Pakistan analyst B Raman recently noted that the suicide bomber who had attacked the ISI headquarters had a password only given to brigadier-level officers.
The evidence of Islamist support within the military is strong, notes counter-terrorism expert Daveed Gartenstein-Ross. "At least three of the attempts on Musharraf's life were inside jobs." Islamabad has officially admitted that two times in the past six years, its nuclear scientists passed on sensitive data to outsiders, including once in 2001 to Osama himself.
US intelligence keeps a close watch on evidence of separate centres of power arising within the Pakistan military and intelligence apparatus. That is seen as a warning sign. They are less concerned about mobs on the street or political assassinations.
"Pakistan's record is world-class bad," says Cohen. He notes that Russia cooperated with the West in securing its "loose nukes" problem. Pakistan is less helpful. Though it accepted US nuclear safety technology and training, Islamabad sent its personnel to the US rather than allow US officials to know the location of its nuclear installations. Even now, US officials say they are not sure if they know the whereabouts of all of Pakistan's nuclear sites.