Is Thanksgiving the most shameless holiday?

The origin of Thanksgiving Day is that when the United States was not established, immigrants who just arrived in America had no land and no food, and they survived with the help of Native American Indians. This festival was created to thank the Indians, but of course it didn't exist at that time.

The reason why this festival is a bit shameless and disgusting is that in the later period, immigrants gradually learned the American way of life and gradually forgot the help of Indians. With the increase of immigrants, the friction with Indians increased, violent bloodshed broke out, and even war broke out, and a large number of Indians were slaughtered. Gratitude turned into conquest.

But the fact will not change. Thanks to the relief given to immigrants in India at that time, Thanksgiving Day came into being. But I think history should bear in mind that Americans should not only be grateful, but also repent for what their ancestors did on this festival.

But sometimes I feel that there are too many bloody incidents caused by cultural conflicts between different ethnic groups, and they can't tolerate each other. But what's the difference between the history of human civilization and the laws of natural evolution?