I read this article yesterday morning and I was really impressed by it. Basically, Pakistan hates India because Pakistan is obsessed with extending Islam and sees India and its success as a rebuke to the nutty goals of Pakistan.
The article points out that Pakistan devotes a huge amount of its budget to its military, which has defeated any attempt by political leaders to change the country’s direction.
The British seem to have been very bad at dealing with the problem of Islam in their colonies. In many ways both Israel and India reflect the fact that partitioning an area and handing one part of it over to the Muslim element was not a successful way of dealing with the problem, if only because Muslim societies are incapable of succeeding and also never drop their desire to take over the entirety of the area for their insane, dysfunctional death-cult society.
Actually, the British succeeding in ending Muslim dominance of the Indian sub-continent when they took over.
So much that in the end those elements of Islam hightailed it to Pakistan.