Maybe many of them just aren't pro American. In almost every other country the media/politics carefully try to project some national pride and sense of unity; it's actually the opposite here in the US isn't it?
If you do or are supposed to feel some guilt or sorrow or shame for the bad, then you could feel some pride or happiness or thankfulness for the good.
Here in France we only just now had a president recognizing our role in the Rwanda genocide, which happened 20 years ago.
Overall I'm seeing a lot more people calling for being proud of our nation and moving past inconvenient historical details than self-flagellation.
Macron is an exception in how much he stands for the "duty to memory" thing. Most people are fine believing their country can do nothing wrong.
But they absolutely do love to push the moral and economic burden for such things on to the common person.
And of course people are proud of their country and history and societies because that's normal healthy part of the human condition. This behavior and thought is increasingly shamed and bullied though.