It appears to me that our society is currently threatened by a group using the exact strategy that those Nazis were using in your home country, except they're at the next stage, past the using free speech and actively now attempting to destroy it.

I'm of the belief that to protect your free society you protect it's virtue, even when people take advantage of it. If you hold steadfast to "free speech", no group ever gets past that first stage, so they can never take power. It means sometimes tolerating hearing reprehensible views of the world, but it is either that or giving someone all the guns and the power to control what you say, and if history teaches us anything, that always ends badly for the regular people no matter the initial intention of the person doing the censoring, a power like that is irresistible to those who want to use it to benefit themselves.