They very cleverly use our tolerance against us: in every Western nation mosques have been the covert terrorist meeting places and planning HQs.
If HItler had called Naziism a religion, would we have permitted Nazi "priests" to build Nazi "temples" across America in the 1930s?
What a concept. Actually Hitler was very clever at using symbols and rituals but stopped short of declaring Naziism a religion. But in the 30s, we weren't as stupid as we are now, so no, I don't think we would have allowed Nazi temples. Today? Terrorist mosques dot the landscape. Tolerance may be our downfall.