He's being down-voted because it's whataboutism. It's no different than the 50 Cent Army that suddenly cares about Native Americans when the topic of the Uyghurs comes up. Yes, the red scare was bad, yes the US's treatment of indigenous people was bad. Everyone agrees about this. There's no school district in the US that uses a history textbook that says the Sioux deserved it and McCarthy had the right idea. The fact that similiar bad things happened in the past does not excuse them in the present. If anything it makes it more reprehensible that they happen today despite the example of what to do.