In 1953 President Eisenhower created the National Defense Service Medal, which is an award given to any member of the Unites States military who serves honorably during a designated time of national emergency. The award has been given for the Korean War (June 27, 1950 - July 17, 1954), Vietnam War (Jan 1, 1961 - Aug 14, 1974), Gulf War (Aug 2, 1990 - Nov 30, 1995) and the War on Terrorism (Sep 11, 2001 to current).
Despite its longevity, it is considered a low-ranking medal for wear and display. The only requirement to receive it is that you are serving during the designated time period. In fact you could enlist and receive an entry-level discharge the next day and still receive the medal. Due to its large distribution and limited value, there are many on eBay without any bids. The oldest service decoration still in circulation by the United States armed forces is also the least valuable one.
-Professor Walter
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