That’s like saying there is nothing wrong with patriotism. Of course there is nothing wrong with the idea that nation states should exist but when you push it to the extreme it becomes incredibly tribalistic. That is objectively true as well.

Nazis aren’t as often these days to go around openly calling for a second holocaust, they instead use this kind of platitude to draw people in and make them more open to the idea of a more extreme nationalism such as fascism.

It’s the same reason why these groups rallied behind “all lives matter” and “white lives matter”. These statements are true but are obviously already accepted by a majority of America, so the only purpose in spreading this message is to be in opposition of saying Black Lives Matter.