I have to disagree. Nazi's and other people of ugly opinions have as much right to voice that as anyone else. We have laws against actions that should cover whatever ugly they get up to.
Organization is a presule to action. Laws have a deterrent effect but they are not always sufficient. If laws were sufficient in and of themselves, atrocities and military conflicts would never occur.
Note that I'm talking about defeat in the rhetorical arena here. It's important to make it clear that Nazis are not merely bad people but also wrong & stupid -- otherwise, people who don't mind being bad so long as it benefits them will keep becoming Nazis.