World War III

World War III (WWIII or WW3) and Third World War are names given to a hypothetical third worldwide military conflict subsequent to World War I and World War II. The term has been in use since the end of World War II. Some have applied it loosely to refer to limited or smaller conflicts such as the Cold War or the War on Terror, while others have operated under the assumption that such a conflict would surpass both prior World Wars in both the level of its widespread scope and of its overall destructive impact.

Because of the development and use of nuclear weapons near the end of World War II and their subsequent acquisition and deployment by many countries, the potential risk of a nuclear devastation of Earth's civilization and life is a common theme in speculations of a Third World War. Another major concern is that biological warfare could cause a very large number of casualties, either intentionally or inadvertently by an accidental release of a biological agent, the unexpected mutation of an agent, or its adaptation to other species after use. High-scale apocalyptic events like these, caused by advanced technology used for destruction, could potentially make Earth's surface uninhabitable, what prompts many to believe that after the war, humans would live either in underground facilities or in colonies in space (such as on the Moon or Mars or in a space vehicle).

Prior to the advent of the Second World War, the First World War (1914–1918) was believed to have been the "war to end all wars," as it was popularly believed that never again could there possibly be a global conflict of such magnitude. During the inter-war period between the two World Wars, WW I was typically referred to simply as "The Great War" and was almost never referred to as the First World War. Unfortunately, in 1939 the outbreak of World War II disproved the hope that mankind might have already "outgrown" the need for such widespread global wars.

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