Nukes, check.
Terrorists, well, on the wrong side of the law (so far).
Nuts, no. Musharraf is so far not nuts. The face off with India showed that he's no hair trigger on his WMD. Saddam in a similar circumstance would have an unacceptably high probability of launch.
Were Pakistan to go jihaddist instead of military dictatorship (odious enough), the I would agree, and preemption would be required.