Muslims do a ton of locally based mission/charity within their own communities. Though I agree for the most part that Islam is by todays modern standards the worst of the "big 3", if you will. However, christians have done, and will continue to commit acts of "terrorism" all their own. Anytime someone truly believes that they're "gods special little guys/gals", and that nonbelievers don't qualify as people, you have yourself a very dangerous person indeed. This is regardless of the faith involved, its a basic self-declared sense of elitism. I believe "x" and you do not, therefore you are useless/worthless.
Your comment about a "godless" society saddens me, and reinforces my previous statement. I would much prefer a society free from the division of organized (militarized) religion. It is true that many of our laws seem to mimic some of the 10 commandments (well the ones that aren't completely moronic, go ahead read em again) but most modern societies stress similar belief systems without the help of the bible. Loving your family, not killing your neighbors, not stealing, these are all things that most modern (and even basic, tribal) societies tend to believe. Its the same basic herding/social response we see in most animal groups. Surivial through cooperation.