Paul Taucher and Dr Dean Aszkielowicz argue that war crimes justice does not work the way commentators generally suggest it does. AFTER THE SECOND World War, the victorious Allies prosecuted German and Japanese civilian leaders and military personnel for war crimes. The decision to hold these trials was based partly on a belief that the decades prior to the war had seen a genuine awakening among nations that some rules should apply to the conduct of wars and that efforts must be made to avoid devastating conflicts.

Source: The problem with war crimes law and what needs to be done