Why do Muslims blow other Muslims up what sense is this?

I barely consider these suicide bombs news anymore. Its equivalent to the West saying, Harry walked to the tube and went to the city. Someone else wrote that there are many types of muslims... True. They are not even tolerant of them selves let alone the West. We sure have open arms though, huh. Side question, how long do you suppose it will be until the headline has london, new york, toronto in it?