British rule curbed ethnic and religious tension in India? Wow. That is like saying communism increased the private sector in Russia after 1917. If the British did do that, why was Pakistan demanded and created BEFORE the British left?

The British played divide and rule, by setting the two communities against each other. They successfully did this in Sri Lanka (setting Tamils against the SInhalese), Nigeria (Igbos against the Hausas), Burma (Kachins against the Burmans), Iraq (Sunnis against the Shias) and so on.

You really must get an education in world history, not the propaganda the British peddle out. For example, the reason the Brits became rich is because they looted India for 200 years. They took natural resources like gold, diamonds, cotton, spices, tea, etc for free (Indian farmers got practically zero), they stole billions of dollars of capital (Indian taxpayers paid double for every kilometer of rail line, compared to rail lines in the UK), etc.