Individual commentators such as the German historian and left-wing antiwar activist Jörg Friedrich have argued that Allied aerial bombardment of civilian areas and cultural targets in enemy territory, including the German cities of Cologne, Hamburg, and Dresden, the Abbey in Monte Cassino in Italy during the Battle of Monte Cassino, the Japanese cities of Tokyo, Nagoya, Osaka, and especially the use of atomic bombs on Hiroshima and Nagasaki, which resulted in the total destruction of cities and the deaths of hundreds of thousands of civilians, should be considered war crimes; however, other observers point out that no positive or specific international law with respect to aerial warfare existed prior to and during World War II and that no Japanese and German officers were prosecuted at the post-World War II Allied war crime trials for the aerial raids on Shanghai, Chongqing, Warsaw, Rotterdam, and British cities during the Blitz.