I don't like the phrase "at fault" here. Each individual is responsible for his/her own actions. Assuming no evidence of any active collusion by his pals, the only person I hold responsible for the murder is the driver of that car.

I think the collasal failure by Trump was his failure to call out the racism and bigotry firmly situated on just one side - represented in your options by "alt-right". The organizers of the protest. Anyone marching with them was marching with racism, nazism, bigotry. Period. The other side, however inappropriate some of their actions may have been, were there to oppose those things.

This is a distinction Trump did try to draw, in his stilted, scripted presentation on the following Monday. My anger would have been largely muted if he left it there. But of course he didn't. He discarded all that with great passion the next day. I view that as a stunning moral failure on his part.

But "at fault". If I run up on a Nazi alt-right skinhead white supremacist with a metal pipe and smash in his skull, I'm guilty of exactly the same thing that he would be if he did it to me. I think the anti-bigot side needs to be clear about that. If thugs under the guise of Antifa start bashing things, raising hell, beating people, and so on, the law should look at them just as they would racist thugs.