Strange that some Indians here are acting as if the US somehow needs that relationship more than India needs the US.
See this is the problem with threats. If you get called on them, it can be extremely embarrassing when ultimately there is nothing you can do.
If I were a psychologist I would say India is lashing out due to an interesting combination of insecurity and inexperience on the world stage. While it may appear to be an inflated sense of self-worth, I think stating "the world has changed" is very telling.
For such a bright People, some Indians are being immensely short-sighted and reactionary to this story.