Hillary Clinton, the US secretary of state, told Congress recently that Pakistan had dispersed its nuclear warheads to different locations across the country in order to improve their security. But John Bolton, a hawkish former senior official in the Bush administration, said this weekend that this move could have the opposite effect to that intended."There is a tangible risk that several weapons could slip out of military control. Such weapons could then find their way to al-Qaida or other terrorists, with obvious global implications," Bolton said.