I've known Muslims here in the U.S. since about 1980 (all Iranian) and not a one of them has ever blown anyone up. A few have even passed on without doing so. A few have become Christians but maybe that's just cover, right?
It's my belief that many, if not the majority, of Muslims are in fact moderates. (And there are many who are the equivalent of C&E Christians.) The problem is that one can never be absolutely certain which is which.
Just like one can never be certain that the "really nice/good neighbour" isn't an axe murderer, real or potential, on her off days.
OTOH, I have a Muslim colleague who frequently regales his Western colleagues about the "Evil Juice" -- to the point that a German colleague with no love for Israel took him to task a while back.
IIRC, the crazies are usually described as quiet, kept to himself kind of people, although there are always exceptions.
I have not yet met an Iranian (Persian) person I didn't like, but I have also read enough of the Koran to be afraid of muslims/islamic people/followers of the Koran.
Any so called religion that encourages it's people to kill anyone that doesn't agree with it, is not a religion in my books, and it doesn't deserve my respect.