NEW DELHI: The Taliban attack on Pakistan's Mehran naval base raises an oft-repeated question: can Pakistan save its nuclear weapons?Pakistan's nukes evoke a curious reaction -- every leader, in India or US, stress their safety, yet everybody stays up at night wondering whether they are really safe. Pakistan's failure to save its prized maritime reconnaissance aircraft has only deepened the worry.Rahul Roy Chaudhury of International Institute for Strategic Studies (IISS), London, sums up the fears. "The attack on Mehran, a well-guarded military installation, at a time when Pakistan is on its highest alert status following the Abbottabad raid, raises serious questions over the security of Pakistan's nuclear assets. Not merely weapon storage sites, whose locations may be secure, but more likely, nuclear plants and research facilities whose locations are well known. This could be exacerbated by the passing of 'insider' information on their security systems by employees angered and radicalized by the Abbottabad raid."How can Pakistan's nukes fall into the wrong hands? Either Taliban/al-Qaida getting a hold of the weapons, jihadis accessing fissile material which could be used to make a "dirty bomb" or, extremist officials within the Pakistani military establishment itself accessing weapons or material.Taliban/al-Qaida have flirted with the idea of a "dirty bomb" or capturing nuclear assets for some time now. But as strategic experts have said, it's not easy getting a nuclear weapon, leave alone use it. The supporting infrastructure needed is fairly large. George Perkovich of Carnegie wrote, "Pakistan's...nukes are its crown jewels. The army cares about them in ways that it does not about bin Laden's whereabouts or fighting the Haqqani network."Besides, Pakistan's weapons are not holed up in traditional silos. The military keeps them secret, but they are generally believed to be in storage sites (most probably in Punjab) and not in a high state of alert. Pakistani experts say they are also mobile to keep their locations secret. Shireen Mazari, Pakistani strategic expert, dismissed Taliban takeover fears in a post-Osama briefing. "The nuclear programme has matured, is robust, self-sustaining and widely dispersed." It's well guarded, but after a breach at their naval airbase, the question being asked is, how well is well guarded?A new danger comes from the sophistication of Pakistan's nuclear weapons capability. In April 2011, Pakistan showed it could build tactical nuclear weapons with NASR. These are low-yield short range plutonium-based weapons and they are mobile. Which can give Pakistan's nuclear capability the jihadi edge, because they can be transported and used easily. The temptation to use them as a terror weapon just got easier.Pakistan's weapons are controlled by the army's Strategic Plans Division (SPD) under the National Command Authority (NCA). Yet the danger remains of infiltration of the Pakistani military system and legitimate access into nuclear facilities by jihadi elements within. Experts worry that if nuclear weapons are mobile -- say, travelling through Punjab countryside riddled with jihadis -- they may be safe from India or US, but they could be in danger of being "abducted". Scott Sagan, US nuclear expert, laid out a similar scenario, when he was quoted as saying about Pakistan feeling "compelled to take their weapons out of the base, put them with their missiles on their launchers and move them to the countryside" for any reason. "That makes them more vulnerable to terrorist seizure by an outside group or an insider group collaborating with the terrorist groups."That is the outside world's greatest fear. Since 9/11, the US government has apparently given $100 million (perhaps more) to help Pakistan build stronger protection of its nuclear weapons. But apparently the Pakistan government refused the US permission to design electronic locks ("permissive action links" in nuclear jargon) for the weapons, fearing US infiltration into their security. Pakistani officials over the years have stated that they have developed these themselves.