Well, that's the exception unfortunately, especially of you're on the winning side. Even in Germany, which is often held as a prime example on taking responsibility for their actions during WW2 afterwards, quite a bunch of medium to high ranked officials got away.
Another example is Japan. Even fewer were prosecuted and punished for their war crimes there, even though the US were paying close attention first. It became less important after it turned out Japan could be a great ally for the US's involvements in Asia, so a lot of them could get off the hook.
Thats far too easy. In a democracy YOU are the state.
I wonder what would happen if we could live cast our military deployments so that every voter has access to every war crime committed? Maybe then people wouldn't be so quick to sign up for another war. Or they would at least be honest about it.
Watch films and TV shows where blatantly illegal actions - including Geneva convention war crimes - are committed by the heros. I'm not persuaded the public wants less of this. And politicians sometimes play to this, asking for action that's of dubious legality