All religons of the past have committed atrocities. The difference is using the standard of today, modern civilized society to judge actions from hundreds and thousands of years ago. You can't judge them by the same standard as you do in current civilized society.
Was the moor invasion terrible? Yes. How about the Spanish inquisition? Yes. Etc...
Its a dishonest argument to compare events chronologically separated by centuries and a different standard or morality.
I can tell with certainty if Christians now were committing the same violent acts as radical Islam I guarantee they would be called out, disassociated from, excommunicated, etc. No way Christians would tolerate their own killing innocent people in the name of god.
You're a moron.