If we're going to judge an entire genre by its impact on its fans, we owe it to the genre and the fans to examine primarily the bands that have the most fans and therefore are positioned to have the greatest impact. Black Sabbath and later Ozzy Osbourne solo. Consistently affirmative of life, dismissive of hatred and organizations that spread it. Led Zeppelin. Their early work was nothing but electric blues, making me wonder how the heck they ever got categorized as "heavy metal." It must have been their choice of name, a triumph of marketeering. Nothing fascist in that music. Later they jumped into prog rock with its usual cute, unfathomable lyrics. "Stairway to Heaven" is arguably the most listened-to "heavy metal" song ever recorded, and it has absolutely no meaning whatsoever. "When all are one and one is all/To be a rock and not to roll." Come on people, be serious! Metallica. Their early speed-metal tunes had many dark themes, but not one of them, in my recollection, touched on Nazi politics or philosophy. They were more into H.P. Lovecraft than Adolf Hitler. Their later music that won them a huge audience was like Sabbath. If you can find the faintest reference to Nazism in it, it would be as the object of criticism.