Richard Spencer, what a cuck.
Nope, nope, nope. Don't use violence, even against scum like Spencer. Because when you do, you a) put yourself on the wrong side of the law, b) beget violence in return, and c) are admitting that you can't win an argument with him on the merits and have to resort to violence to shut him up. And you a) want to be on the right side of the law, b) don't want them committing violence against you and your supporters, and c) can defeat Spencer or any of his asshole cronies in an argument on the merits.
And anyway, what if you reverse the roles and it's someone you respect being belted by a neo-Nazi? Are you going to laugh at it then? No? Then why are you laughing at it now?