Since you are specifically talking about wars and how those who are responsible for them are not held accountable, you need to understand the complexity of taking a head of state into costudy while he was visiting a different country or something, it would easily unleash negative retributions and escalate the conflict in new ways never imagined. Vladimir Putin is one example of if, actually, there are International courts which have issued arrest warrants against him and in theory those are supposed to be applied when Putin steps into other countries which are part of the International court, however he has managed to go to those countries, like Nepal, and face no consequences or being out in front of a judge to be prosecuted for the alleged crimes against humanity he is guilty of, since he decided to invade Ukraine.
So far, it seems authoritarian leaders con go around the world unpunished, because of the fear they give off and the threat of nuclear escalation.