White supremacists and others on the radical Right like sovereign citizens, anti-tax nutters, and the like are nowhere near the biggest domestic threat to the US. The Progressive Left and radical Left have trotted out this canard since before the Clinton era where we got to see just how insane the radical Left is when it gets power. During the Clinton era, we saw a massive attempt to crackdown on the radical Right. This resulted in the Ruby Ridge fiasco, Waco, arrests of various fringe militia group members numbering in the dozens, and the like. Most of these arrests went nowhere, but the high profile handling of these cases in government and media stirred the radical Right to action resulting in things like the Oklahoma City bombing.
Left alone, the crazies on the radical Right are mostly a threat to each other. They rarely get together to do anything other than in the smallest numbers. Provoked, they can be very dangerous individually and can rack up serious body counts.
On the other hand, the radical Left is far more dangerous on a much larger scale. Radical Leftists like BLM and Antifa produced riots with thousands taking part. They trashed whole city centers, caused dozens of deaths, thousands of serious injuries, and billions in property damage. They wrecked the lives of tens of thousands, at a minimum. In power, they know no bounds and will do virtually anything to retain power.
The radical Right will never come to serious political power. The radical Left has come to serious political power repeatedly during the last century. The results of their coming to power has included world wars, economic privation for billions, the deaths of as many as 100 million--at least--can be laid at their feet. There is no comparison between the radical Right where two or three guys--at most--do some act of violence killing maybe tens of people, with the radical Left destroying whole nations and killing millions.
