What's wrong with an emotional response to an atrocity? Is it irrational to cry over the Holocaust because, hey, the Tsars didn't some pretty bad pogroms, too? No, emotional responses are perfectly fine and are a normal mode of thinking. Your fetishization of reason is dangerous and echoes the same rhetoric that enabled these atrocities: oh, they're not people, they're savages because X, so cut off their hands if they don't bring enough silver. The correct response here is to denounce colonialism, not to say, "oh, hey, it's not that bad because other people have done bad things."