Synagogues, Churches, military recruiters?
I thought pretty much every square inch of the planetary surface was a viable islamic bombing target.
These days it's mostly the non islamic parts that get bombed, but should they -God forbid!- succeed in taking over the world and killing or converting its entire population to islam, they will fall upon each other for 'not being islamic enough'.
Murder in the name of their pig-god is all they really know, the only thing they are good at, and the only thing for which they have any real enthusiasm.