I hate to be contrary, but islam has a lot in common with the communists (marxists/socialists), and you can find very good discussion of why that is true in Andrew McCarthy’s excellent book, “The Grand Jihad”. McCarthy says more in one paragraph than other say in whole chapters.
(Note: proper nouns as used above are not capitalized because I refuse to respect those vile entities of islam, communism, marxism, and socialism.
A low ball estimate for the twentieth century victims of Communism alone is 300 million. Islam has 14 centuries of victims uncounted but I have not seen any figures that suggest that it toll would be higher than that. Also I would not consider honor killings as counting Apples to Apples. I consider honor killings as more a culture norm than a political act.