You're correct, they currently don't have enough concentrated power. But that's the thing, if they did the genocide would begin immediately. No fascist movement came to power instantly, they built their power slowly through a mixture of government-sanctioned and illegal political activity and when they had accumulated enough power, in a quick strike decapitated their respective democratic governments. You can't afford to be reactive here because, by the time their regime starts in earnest, it's already too late. These ideologies need to be destroyed while they're still fledgling, ridicule only works at the very beginning and we're too entrenched for it.