State terrorism has been used to refer to terrorist acts committed by governmental agents or forces. This involves the use of state resources employed by a state's foreign policies, such as using its military to directly perform acts of terrorism. Professor of Political Science Michael Stohl cites the examples that include the German bombing of London, the Japanese bombing of Pearl Harbor, the Allied firebombing of Dresden, and the U.S. atomic bombings of Hiroshima and Nagasaki during World War II. He argues that "the use of terror tactics is common in international relations and the state has been and remains a more likely employer of terrorism within the international system than insurgents." He cites the first strike option as an example of the "terror of coercive diplomacy" as a form of this, which holds the world hostage with the implied threat of using nuclear weapons in "crisis management" and he argues that the institutionalized form of terrorism has occurred as a result of changes that took place following World War II. In this analysis, state terrorism exhibited as a form of foreign policy was shaped by the presence and use of weapons of mass destruction, and the legitimizing of such violent behavior led to an increasingly accepted form of this behavior by the state.