NOTE: The source for some of the following definitions ...

A division is a nearly universal military organization consisting of approximately 20,000 troops commanded by a major general. During the Vietnam War, the following U.S. divisions or elements thereof participated in the War: The First (1st) Cavalry; the 1st, the 4th, the Fifth, the Ninth, the 23rd (Americal), and the 25th Infantry Divisions; ................
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