World War II

World War II, global military conflict that, in terms of lives lost and material destruction, was the most devastating war in human history. It began in 1939 as a European conflict between Germany and an Anglo-French coalition but eventually widened to include most of the nations of the world. It ended in 1945, leaving a new world order dominated by the United States and the USSR.

More than any previous war, World War II involved the commitment of nations’ entire human and economic resources, the blurring of the distinction between combatant and noncombatant, and the expansion of the battlefield to include all of the enemy’s territory. The most important determinants of its outcome were industrial capacity and personnel. In the last stages of the war, two radically new weapons were introduced: the long-range rocket and the atomic bomb. In the main, however, the war was fought with the same or improved weapons of the types used in World War I (1914-1918). The greatest advances were in aircraft and tanks.

The World After World War I
Three major powers had been dissatisfied with the outcome of World War I. Germany, the principal defeated nation, bitterly resented the territorial losses and reparations payments imposed on it by the Treaty of Versailles. Italy, one of the victors, found its territorial gains far from enough either to offset the cost of the war or to satisfy its ambitions. Japan, also a victor, was unhappy about its failure to gain control of China.

A Causes of the War
France, the United Kingdom, and the United States had attained their wartime objectives. They had reduced Germany to a military cipher and had reorganized Europe and the world as they saw fit. The French and the British frequently disagreed on policy in the postwar period, however, and were unsure of their ability to defend the peace settlement. The United States, disillusioned by the Europeans’ failure to repay their war debts, retreated into isolationism.
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