Well, try an historical parallel. Remember how widespread "leftism"was in the seventies? The pendulum has just swung back again.
In the seventies, the Dems were hijacked by extremists, yet their viewpoints were popular among a broad segment of the population. Well, not the actual viewpoints themselves, but rather the “I’ll wear my hair long ans smoke weed at parties and have a Che Guavara Poster in my dorm room and discuss Marcuse over a bowl of sangria” watered down version of it.
The way I see it, the right in the US currently has a similar outburst of popularity with irrational but attractive ideas.
Another parallel is the hostility the left felt, at the time for the right. “Fascist government dogs” almost was a term of endearment. The right didn’t go much further then “damn misguided hippie kids”.
Even those tables are turned. The right is the one foaming at the mouth now; the left in the US currently has the bigger percentage of reasonable people.
Anyway, that is my Dutch take on it. And it is the same in the Netherlands at the moment.