Interesting question; I consider the "world war series" to only be in direct relation to Europe and Asia's "Great War" that lasted from 1914 to 1918. That war was the first. The second world war (1939-1945) was an extension, or sequel, to the first war. Therefore, for it to truly be a World War III, it would somehow have to be connected to this original series of world wars. After nearly 70 years, the US military still occupies Germany, Japan, and South Korea. The Soviet Union collapsed and ceased its occupation of Eastern Europe 20 years ago. I would probably call World War III the Cold War with every military conflict, CIA conflict, and military standoff we had from 1950 to the collapse of the USSR. The US suffered about 110,000 killed in that time period. Major US military battlegrounds were in formerly-Japanese occupied lands of Vietnam and Korea. If there is another world war of this series, it will probably take place in Korea or the former-provinces of the Ottoman Empire--Levant or Mesopotamia. Such a war would either end or begin with the bankruptcy of the US government. I'm thinking 2020s, if at all.