Eliminate all orcs

Well, obviously they can take prisoners. The idea that they ever wouldn't is exactly how that kind of thing happens to begin with.

Refusing surrender is war crime.

Well, not like Ukraine is going to stop piling them up with use of Child Soldiers and sending unarmed civilians to front lines as canon fodder against Russia. Not to forget their attacks on Ukrainian-Russian civilians who became part of Russia. (I mean they been attacking civilians four years prior already, why stop now?)

Stop Russian mass murder.

When the cat's away, it's a regular rat day