Fears grow that radicalised groups in military could gain access to atomic weapons, writes Rahul Bediin New Delhi.
Benazir Bhutto's assassination and the chaos it threatens to bring about raise worrying questions about the continuing security of Pakistan's nuclear arsenal.
Pakistan is the sole Islamic state with nuclear weapons. It is also one where the atomic arsenal comprising, according to experts, between 60-65 warheads, is controlled almost exclusively by an increasingly "Islamised" military that remains the country's most powerful institution.
The location of the arsenals remains a closely guarded secret, but western intelligence sources believe they are secreted in Islamabad's "proximity" and in the northern Chitral region bordering China, with the warheads and delivery systems separated but capable of being "mated" within a short timeframe.
Islamabad's record in nuclear proliferation too is, at best, dubious. Its top atomic scientist Abdul Qadeer Khan was exposed in 2004 as the head of an international black market operation in nuclear technology, reportedly working in collusion with the military, leaking secrets to Iran, Libya and North Korea in exchange for money and long-range missile designs.
Pakistani nuclear scientists are even believed to have travelled to Afghanistan to meet with the al- Qaeda leadership when the Taliban controlled Kabul before being ousted by the US-led coalition in 2001.
However, India and western analysts caution that radicalised elements within Pakistan's military and security establishment "could" gain access to the country's nuclear weapons if the debilitating war of attrition against the jihadists continued.
They cite the instance of a large number of Pakistani soldiers, including officers, opting to surrender to militants rather than fight them in the tribal regions bordering Afghanistan and in Swat, north of Islamabad, as an instance of the military's burgeoning radicalisation.
These are growing signs of "fraying" loyalties in the Pakistani army with its normally robust command and control system appearing "wobbly" and underlying the danger to its "cohesiveness", say analysts.
"A situation threatening the security of Pakistan's nuclear arsenal and collapse of its command and control could only be brought about by subversion from within the military establishment," said former brigadier Arun Sahgal of the United Service Institute in New Delhi. "Were this to happen it would signify the Islamists' penetration of the last bastion of credible power in Pakistan, a situation that frightens the world."
Earlier this month President Pervez Musharraf assumed formal control of the National Command Authority that he established in 2000 to manage the country's nuclear weapons, two years after Pakistan detonated six atomic devices.
The National Command Authority includes the associated Employment Control Committee, the Development Control Committee and the Strategic Plans Division, all overseen by a select group of officials, dominated by the military.
As the names suggest, the Development Control Committee deals specifically with the planning and development of nuclear forces, while the Employment Control Committee deals with what can be defined broadly as "nuclear strategy" including targeting policy and the conduct of nuclear operations.
"But it would take little time for the command and control network to collapse if Pakistan slid toward anarchy. Should that happen, sympathisers of radical Islamists within the Pakistani military and intelligence agencies could very possibly assist militant groups in acquiring the wherewithal of a nuclear weapon," said Harsh Pant, a nuclear analyst at King's College in London.
Last month Pakistan confirmed that the US was helping to ensure the security of its nuclear weapons, but declined to elaborate. It reiterated that the security of Pakistan's nuclear assets was "foolproof" and advised against creating irresponsible alarm. In an official statement it declared that it was capable of defending its nuclear interests and cautioned those "contemplating misadventures".
Meanwhile, US media reports said that Washington had spent $100 million in helping to secure Pakistan's nuclear weapons against theft and accidents, a claim Islamabad denied.
Some western experts believe that the US fitted Pakistan's nuclear warheads with permissive action links or security devices that control their activation soon after aligning with Islamabad in the war against terror following the 9/11 attacks on New York and Washington. Pakistan refutes that claim also.