Well I'm not going to deny that the U.S. doesn't have a history of far-right extremist groups which can range from the historical examples such as the 'Ku Klux Klan' to the unhinged far-right extremist groups that you can find on the Internet in the present day then.
However, my issue that I have with the left is that they refuse to acknowledge that they also have a history of many acts domestic terrorism and extremism in various Western countries.
The best example that I can think at the top of my head is the 'Weather Underground' organization which was at the time this far-left organization that had dedicated itself in overthrowing the American government and establish a new communist state. They did things that ranged from committing arson attacks towards the homes of government officials and a university to actually bombing the Pentagon at the time. This group was an unhinged hippie group that wanted to take matters into their own hands because they believed at the time that they were "fighting fascism" when really they only harmed lots of people in the process.
So the way I see it, I can really see the 'Black Lives Matter' movement become more and more batshit insane and eventually devolve into Weather Underground 2.0 and we'll probably see them start a ton of shitshows in the process then.