The Green Beret
One of the distinctive symbols of the special ops, the green beret, also has its origins in the British secret military. The distinctive headgear was awarded to U.S. Rangers and other intelligence operatives who had completed training with British commandos. The graduates of these courses would wear the berets as a badge of honor, though they were officially not part of the U.S. military uniform, until President John F. Kennedy — who recognized the high value of special ops units — authorized their use in 1961. In this photo, an Army captain wears one of the green berets while taking target practice in Vietnam in 1964. One year later, the hats would gain a special place in American military lore with the publication of the bestselling book, The Green Berets, that detailed the unit's activity in Vietnam, and led to a 1968 movie starring John Wayne.

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