Why are some fundamentalists driving a wedge between Christians and Muslims?

I am a Christian and I do not hate Muslims (but I do not agree with their theology either). But I do not believe that they are evil just because they have a different religion. There may be some extremist Muslim fundamentalists who want to start Jihad (and I think they are evil) but I think they are in the minority. But I am a bit disturbed that among Christians, there are also a similar group of fundamentalists who are promoting hatred of Muslims. I see extremism, whether Muslim, Christian...or even Jewish, to be evil.