> If we look at the founder of Christianity, there is no advocacy of using violence to achieve ends. So, the claim of that KKK and other violent groups are Christian doesn't hold much water. This is not to say that an individual who espouses a certain belief will not be violent, just that the religion is not the source of it.
> If we look at the founder of Islam, we see something else. We see violence and coercion used and advocated by the founder.
Who gives a damn? Most religions are full of contradictions, you pick the bits you like the most. "Non-violent" Christianity was behind major milestones of human progress such as the Crusades, the repression of the Cathars and Albigeois "heresies" (who do you think came up with "let God sort them out"?), the Spanish Inquisition...