Do other people at the protest say “hey buddy, that’s not what we’re about”?

Or do they look the other way?

There have been movements in the past where a minority of the movement was antisemitic while the majority of the movement just looked the other way on the antisemitism from the others. It didn’t go well for anyone.

The paradox of tolerance. If you tolerate the intolerant in your movement, you’re part of an intolerant movement.