I've been reading a book about ethics, and it occurs to me ethics isn't just about what's right and wrong, it's about which issues are treated as ethical issues. Often we're told either to stop taking something too seriously, or that seeing it ethically is childishly idealistic.

Behavior that's obviously morally wrong to me—the person harmed—is often dismissed by the person responsible as a joke, or something everyone does, or a trivial failure of courtesy. The person responsible behaves as if it's ridiculous even to treat it as an ethical issue.

It's also common to reclassify an ethical issue as a biological issue: we're told some behaviors are natural, the neutral result of evolution. This places them outside the ethical realm, allowing people to evade the question of whether they are wrong.