A third example of the controversies with which Kelsen was involved during his European years surrounded the severe disenchantment which many felt concerning the political and legal outcomes of WWI and the Treaty of Versailles. Kelsen believed that the blamelessness associated with Germany's political leaders and military leaders indicated a gross historical inadequacy of international law which could no longer be ignored. Kelsen devoted much of his writings from the 1930s and leading into the 1940s towards reversing this historical inadequacy which was deeply debated until ultimately Kelsen succeeded in contributing to the international precedent of establishing war crime trials for political leaders and military leaders at the end of WWII at Nuremberg and Tokyo.