"why are the white supremacists the only ones on top of these issues?"I don't speak for or on behalf of white supremacists, but probably because other than on the Jewish question, Xymphora is an indoctrinated lefty, I think he completely misunderstands what white supremacism really is. Thus, my response:
I think what you are referring to as "white supremacists" is the fledgling white consciousness movement that is rising up in reaction to Jewish supremacists and La Raza-type racists -- who themselves are emulating the Jewish supremacists.
Once you understand that Nazism was largely a reaction to and mirror image of Jewish Bolshevism (Leftism and Communism themselves originally being elaborate Trojan Horses for Jewish supremacism) you will comprehend the phenomenon as an inevitable dialectic and outcome of the “original sin” of Jewish supremacism.
Why is the Left in general and left-liberalism in particular so gun shy about identifying and openly rebuking Jewish supremacism outside of Israel? Because the Left is built upon a vision of a patchwork of tribal, Jewish-like entities uniting to smite Christianity and Western Civilization -- a vision inspired by Jewry to begin with. Jewry is the Left's linchpin and key to the "intellectual" Left's agenda of nihilism, and always has been. But Jewry has played other Left tribes for the useful idiots they are, just as it played the Buschcons.
Jewry simply takes to an extreme what all tribalists seek to do, and what all stunted tribal elements that comprise the Left (and yes, the Statist-authoritarian Right, too) will ultimately attempt when allowed enough power: homicide of the “other.”