I'm not sure I understand your question. Is what true? I don't think the ACLU actually supported the Nazis in Skokie or their message. But sometimes people miss the forest for the trees with that case. In oder to defend your own rights, you have to defend everyone else's rights too. First they came...
But the ACLU has changed quite a bit since those days it seems. It's my understanding that they no longer take the "sunlight is the best disinfectant" approach to free speech and the free and open exchange of ideas.