If someone is marching around in jackboots and a swastika armband talking about how we need to invade Poland, then it is indeed appropriate to invoke Nazism. And if someone is advocating that people should be blackballed in an industry purely because of their unpopular but also completely unrelated political views, then it is indeed appropriate to invoke the Hollywood blacklist.

Anyway, we're getting way off my original point, which was that this weapon of yours doesn't care who it's pointed at. Once you've unleashed the blacklisting, it'll get used against people you don't want it to. As has happened here.