WITH political instability spreading, nervous concern has mounted over the fate of Pakistan's nuclear arsenal should Taliban sympathisers gain power within the military, but under the terms of secret agreements, US personnel have been stationed in Pakistan whose sole function is to guarantee and secure the safety of Islamabad's nuclear arsenal and keep it out of the hands of terrorists, according to several serving and former US officials. Some of the American technicians have had direct access to the nuclear weapons themselves, these sources said, reports Washington-based Middle East Times on Friday. The report was authored by Richard Sale. Pakistan's nukes are currently secure, in the opinion of several former and serving US officials. "They are for now," said one. In 2000, the Clinton administration created a joint commission, a 'liaison' group, consisting of top American and Pakistani scientists. The purpose of this group was to help the Pakistanis create command and control codes for its nuclear weapons that would be unbreakable. One former senior US intelligence source told the newspaper that in the course of such work, America gained 'a pretty full knowledge' of Pakistan's command and control system. The United States then used Special Forces 'snatch teams' to kidnap Pakistani scientists who were allegedly peddling nuclear technology or knowledge of it to undesirables. A group of such scientists was abruptly disappeared while travelling in Burma, these sources said. In addition, the kidnappings disrupted an alleged 200 links between the Pakistani nuclear community and terrorists with ties to Al-Qaeda, they said. After two days of the 9/11 attacks, under US pressure, Pakistan's military began to secretly relocate critical nuclear weapons components to six new secret locations, US sources said. Warheads and delivery systems, which were already being kept separated, were put even more widely apart, and additional surveillance was put on Pakistan's nuclear labs and their personnel, they said. Additional steps were also taken to separate fissile material from the labs or the weapons themselves, they said. More US 'technical advisory' teams, many staffed by Defence Intelligence Agency or Energy Dept intelligence officials, began to appear in Pakistan along with warning and assessment equipment. Communications systems between Pakistani nuclear commanders and nuclear storage sites were reviewed and modernised, and certain key nodes were, at some point, on a US target list, sources said. Thanks to US technical means, the United States became aware of defects and miscommunication between Pakistani military centres of command during atomic tests which helped US analysts to grasp facets of Islamabad's command and control areas that were of dubious reliability. Following 9/11, when US advisors persuaded Pakistani scientists to adopt some key features that add security to US nuclear command procedures, tension rose over whether to install Permission Action Links (PALs), an electronic lock that renders a weapon null and void until political commanders relinquish control of the special codes that allow the weapon to be turned on, several sources said. In addition, the weapons could not be used without employing a dual-key system, meaning that a single rogue commander could not initiate their use. In brief, the PALs would prevent the unauthorised use of a nuclear weapon by an aberrant member of the military, and they would prevent use of such a weapon by terrorists, and therefore are important, US officials said. Yet disputes arose immediately. There were legal implications about sharing such sensitive military technology with a foreign power, and some senior US officials balked at using the PALs, thinking they would give the Pakistanis too much insight into America's own nuclear war-fighting system. "The Pakistanis are smart. What they can see and examine, they can re-engineer," said one. For their part, the Pakistanis feared that American scientists would insert a 'dead switch' into the PALs, which would freeze the weapons if someone attempted their use.