I ask this question rather seriously.
You quickly learn US vs THEM and which is which.
Then you learn that it is THEM who will die. And not just die! They'll be cut down in the streets with blood running in the gutters!
We learn about sheep and goats and hold our nose as we drive past a church.
We learn to value only our own group and not even flinch when those "others" suffer. They deserve it, after all!
Labeling and branding and condeming is an important part of hating.
I heard a JW elder say once that Jews deserved the holocaust because they participated in the covenant with Jehovah at Mt.Sinai and accepted the "blessing and the malediction". By not keeping the law of Moses perfectly and by not accepting the Messiah, Jesus, they brought the malediction (curse) upon themselves rightly! I guess somebody like Mel Gibson would agree.
Dismiss homosexuals, human suffering and higher education as part of Jehovah's plan.
Christians and Muslims and Jews can love and kill in the same heartbeat with equal blindness to what binds them as human beings.
Secularism is no different. Humanism has no better track record to offer; atheists are as bloodthirsty as the rest.
Religious people are no worse, but, believers are no better at all. They just talk a prettier talk while walking the same walk as everybody else.
Religion gives us reasons to love but--doesn't it also give us an excuse to HATE?