Are We Stuck With A Permanent Radical Left?

I dunno.
If I had to bet, I'd bet that liberalism will, at some point, reassert itself against the illiberal left, and squeeze the latter back toward the fringe. But I do fear that we now have a significant, semi-permanent extremist left. What's the state of our extremist right? I have no idea. It kinda poked its head up for awhile, but Charlottesville was a debacle for it. It's probably out there, but has few outlets. Even the craziest lefty nonsense can get a hearing on the left--and will always have a place in academia. Even lots of not-at-all-extreme conservative opinions can ruin your career and even your life. So that stuff is probably just out there festering somewhere.
But I haven't given up on some kind of swing back to centrist liberalism.