Independent America was way worse to the natives than the English colonies. Most natives sided with the English, and with the 1763 proclamation settlement was forbidden to the west.

As someone else said- the British weren't half as bad as the AmeriKKKans back then. The Brits and other Europeans started it, but the US perfected the formula by adding genocidal ethnic cleansing (which the Brits and others would go on to copy elsewhere, like Canada and Australia).