Some forms of bigotry become very dangerous. The obvious example was in the 30s, when Jews were targeted by right wing nationalists. But this was going on in the middle of desperate economic circumstances, with massive unemployment and inflation in Germany, so the two together became (literally) lethal.
We don't have that economic disaster today, so at the moment, I am fairly optimistic that the attacks on Muslims will not lead to a 30s type solution. However, this depends on a robust economy; if this went down the pan, then I would expect fascism to take advantage, and Muslims would be a prime target (and scape-goat). But there would plenty of other targets, e.g. trade unions, people on the left, Jews, black people, etc.