This is a very poor comparison. Why should the average American, or ANY American prevent the organization of a group that believes in white power, or any other kind of power? Believing in white power is perfectly legal - so long as you don't say...lynch anyone. If you want to get together and burn some crosses in Billy-Bob's back yard, then whatever man, be stupid. If you want to lynch a black person - you can damn well bet the American people will get involved - through the police and sometimes through legislation (hate crimes legislation anyone?). America does something about these groups, when they are legally able. And the mainstream society does not sit by idly when these attacks happen.
What kinds of things get Muslims in the streets, gets them fired up enough to protest and say, "THIS IS TOTAL BS!" Well, it isn't terrorism. But, OH MY GOD, should disrespect Mohammad, STAND THE HELL BY! We're gonna protest, kill a few nuns, burn some embassies. Yeah, real peaceful religion. This is the kind of crap children engage in (in terms of pettiness). Time to pull up the big kid pants and act like FUCKING ADULTS!
Kind of like that comic a few years ago.