India should be a staunch US ally, can't really understand why it isn't. We had two major office buildings blown up by Islamist terrorists, they had a bombing/mass murder in their equivalent of the Capitol Dome by Islamist terrorists. They also experience Islamist terror in general just about on the same level as Israel.
They are a democracy and they face the same terror threat we do, if not more so with Pakistan on its border and the Arab lands just a couple of doors down, and Indonesia and the Southern Philippines just off to the Southeast. They are also much more within range of potential delivery systems for Iran's nukes.
And, if they do start attempting to make inroads in the Middle East, they'll become another target of the same anti-infidel demagoguery we are and terrorism within India will very likely increase, at least after the ME countries sober up from their Anybody-But-America honeymoon phase and realize India is an even bigger infidel-based democracy than the US.
So I don't get why there is any daylight between the US and India at all. We should be Siamese twins.
I think India is an ally.
India has its own ambitions in the region. During Indira Gandhi's reign, Indian forces came close to launching an attack on Diego Garcia, in order to annex it. India's approach to foreign (and economic) policy is more zero-sum than Uncle Sam's. They tend to flatter developing countries and give Western countries the finger. It's part of the Indian conceit that Western imperialism was the worst thing to happen to India. Being part of the West, the US is, of course, on the firing line.