This is just a guess, but at that time, white Americans were by far the majority, and held all the power, whereas today, they're on the verge of becoming a mino

This is just a guess, but at that time, white Americans were by far the majority, and held all the power, whereas today, they're on the verge of becoming a minority. However, there is no absolute majority coming: there's lots of different ethnic groups, with European whites and Latinos probably being the two largest, with Blacks after that, but many other various groups too. So people don't really feel related to each other any more, I'd say: they're all just people with roots from around the world, who happen to live there for various reasons. In response to the sister comment about Blacks and Native Americans feeling more American, my guess is that, though they were victims of the abhorrent racism of the time, they also believed in the dream of America and had huge hope that this issue would be resolved, at least for their children or grandchildren. Overall, I feel like Americans don't really have much hope for future generations any more.