Alright let's analyze the issue pragmatically. US's policy to make an "evil" country back to normalcy is by "Changing its leadership". That sounds reasonable. So if Iraq didn't have a leader that would listen to the US, they go and do "regime change". This isn't working well in Iraq but that's different issue. US also did a regime change in Afghanistan 'coz Afghan leadership supported terrorism and more importantly weren't ready to listen to the US. There is a subtle difference between the two.
Now if we consider Pakistan's case,
1. US has no reason to initiate a regime change in Pakistan -- 'coz Musharraf is already officially listening to the US. In US's eyes there is no better US friendly leader in Pakistan than Musharraf. 2. At strategic level Musharraf never goes against the dictates of Western powers. 3. Even if US bombs Pakistan next and decimates the country and say installs a puppet government in Pakistan with US army guarding Islamabad.. I don't think it will stop the ISI/Pak army hardliners (may be even terrorists) from following their ideology.
My reading of this geo-political situation is 1. US hands are tied, it's clueless and is playing its best bet by supporting Mushy. 2. India's best option is to build strong defence and to play smart politics with Mushy the backstabber as long as he rules Pak.
We all have to understand that the current terrorist problem cannot be solved by the rulers of nation states by talking to each other. This has become a strong cultural, religious and political conflict between societies, communities and races. National boundaries have become meaningless. Rational and reasonable people have to start communicating with each other to defeat terrorists.
