I disagree. Carelessness with his nukes is the last thing he can demonstrate. Furthermore, just because he can build a bomb doesn't mean that he has many of them. He needs every one he can get as deterrence against those warmongering Hindus next door.
More importantly, Musharraf, like all politicians, wants to stay in power. Much like Saddam Hussein, war with us is the very worst thing for his cause, with the difference being that our current leader doesn't have a psychological need to invade him at all costs, and a war department that's itching at the chance to bomb somebody. We don't want trouble, and neither does he. All we need to do is to make sure that being involved with us won't get him tossed out, which has been his strategy all along. He'll grumble for the sake of his popularity, but in the end it'll just be business as usual.