Where is the West going to get the manpower to go grab the weapons?  And that also works with one of two assumptions: (1) that the Pakistani military is simply going to allow them to do this, or (2) that the western powers are simply going to do away with the Pakistani military -- again, with what manpower? -- in order to get at the weapons.  Neither of these options seems incredibly likely, especially if there is the possibility you noted of India moving.  (India might like to do this, but I don't see it happening.)

Conservatives want live babies so they can raise them to be dead soldiers. - George Carlin