The Safety of the Pakistani Nuclear Arsenal

Russ Wellen published an article in the Asia Times today taking an in-depth look at the safety of the Pakistani nuclear arsenal.  The article outlines a number of steps that Pakistan has taken to ensure the security of its arsenal and takes issue with some of the statements made by David Sanger in his recent piece about Pakistan.  The recent tension with India, however, has resulted in Pakistan moving their weapons to the less secure western part of the country. Longstanding fears of an overpowerful ISI and extremist sympathizers still exist to some degree despite efforts to reduce the problem.  One argument for safety, that the United States could simply send in troops to secure the weapons, is thoroughly discredited.  Jane's writer Brian Cloughley is quoted as saying, "It would, indeed, be a bloodbath if any attempt were made to insert special forces. How anyone in their right mind could even suggest such a scenario is beyond me."  In discussing ways to help reduce the threat to Pakistan's nuclear weapons,  Professor Gregory of the PRSU explains,

Pakistan's biggest problems continue to be (a) the over-powerful role of the army/ISI and (b) that the army/ISI continue to support terrorism/extremism as instruments of state policy. There can be no meaningful progress for Pakistan until [this changes.]  Outside agencies - like the United States, the United Kingdom and the European Union - can keep up the pressure for this kind of change but ultimately it is the people of Pakistan who must decide what they want Pakistan to be and what role they want the army/ISI to play.

What, if anything, can the United States do to increase the security of the Pakistani nuclear arsenal? What are the prospects for increased safety and security of their nuclear weapons?