It's long past time to stop referring to the masked street thugs as "extremists" and instead begin charging them with terrorism. Particularly in Berkeley, a large part of the problem may lie with their mayor, who is himself a proud member of "By Any Means Necessary" and associates with Antifa, which is clearly a terrorist group as defined under federal law:
The U.S. Code of Federal Regulations defines terrorism as "the unlawful use of force and violence against persons or property to intimidate or coerce a government, the civilian population, or any segment thereof, in furtherance of political or social objectives."
When these folks are setting fires, throwing bricks, bashing things and people with bats, hitting people over the head with bike locks and are now discussing among themselves the need to add guns and knives into the mix, they need to be prosecuted as the terrorists they are.
"Not getting disarmed is a big part of the problem, yes, but we need more than flags and bats," wrote one in the r/anarchism subreddit community page.
They're apt to get themselves hurt.