I think its a given that America's impartiality will be increasingly questionable on the issue of Pakistan-India relations as more and more Americans of Indian origin get into these positions of influence. However, had the roles been reversed, American Pakistanis would be doing the same so this is par for the way things are done in American politics. But the downside is that the American stick, tinged with American-Indian perceptions of Pakistan, can only go so far.
Come to think about it, if Pakistan is isolated by the US side with MNNA status being stripped and even if the designation of State Sponsor of Terrorism by the State Department is applied, would it change Pakistan in any significant way? I don't think so. Yes Pakistan would be deprived of foreign assistance from the US and the West, but Pakistan has sufficient friends in the Muslim world and Chinese support to keep the wheel churning along as it has in the case of Iran. It won't be pretty, but it won't be dire either in my opinion.
The calculus that needs to be run is whether the benefits outweigh the risks of going down this path. If the calculation is that indeed this is a risk worth taking, then Pakistan could potentially let things roll downhill. It may not want it, but if push came to shove, it would stick to its red lines.
you already have an air corridor connecting you to them which can be used to transport tanks and personnel; and Cha cha cha baahar will be up and running by the end of the century. What have you got to fear 
