> Native Americans had relatively benign relationships with the settlers, while the latter were weak

Translation: Native Americans were nice to the European settlers, until the European settlers were in a position to murder and expel in the Native Americans. The genocide against the Native Americans happened both before and after the founding of the United States, which casts serious doubt on a claim that the US has a "moral" mission.

> Slavery was not supported in half of the initial US of A,

Not sure where this math came from. Slavery was legal in all 13 colonies at the time of the revolutionary war. It wasn't until later, and in some cases much later, that the so-called "free states" actually freed slaves.