I suspect there are a similarly secular breed of Muslims who think Islam means, "Oh... you know... be nice to people... and... uhm... don't eat pork!" and that's about it. I'm aware that these people are not the enemy. (Heck, most of them aren't even sure what direction Mecca is in and would turn in circles like an Irish Setter if you told them "time to pray!") And that's fine.
But those violent individuals who would kill for Islam are fundamentalists in the truest sense: these are the fundamentals of Islam and they are following them to the letter.