Something to note regarding recent US and Indian history - During the cold war, India supported Russia (Not much of real support, mostly supporting in words and buying technology from Russia in turn). So US ended up supporting Pakistan and China. Pakistan continuously tried different ways to discourage India's development.
Not sure if all that had any major effect on the cold war, but it certainly had serious repercussions in current Middle East wars and soured US relationships with India.
With China and Russia as a threat now, US may be trying to appease India to balance out the powers here. Plus India no longer closely associates with Russia.
Seperately, India is trying to stand up on its own feet with a strong economic growth and there is political and public will to support India's growth with the rise of Modi, AAP and the young educated/worldly generation.