Fundamentalists misconstrue the teachings of a religion. This is not the fault of the religion. A thing doesn't become bad in itself because it is often abused. As such, religion isn't bad just because fundamentalists are stupid. This is very debateable indeed. For the most part, fundamentalists often stick the bare essentials of a religion with as little interpretation as possible (hence the 'fundamental' part). I would argue they are, in religions such as Islam, more true to their religion than the apologists, whose adherence to scripture (in the Abrahamic religions I know a little of) tends to change with the times. Extremists that go above and beyond that which is written in their religion, on the other hand, such as the Spanish Inquisition, are not fundamentalist but merely extremist (or so I think).