Well, according to Wikipedia:
"In the United States, Armed Forces Day is celebrated on the third Saturday in May. It falls near the end of Armed Forces Week, which begins on the second Saturday of May and ends on the third Sunday of May.
"The day was created in 1949 to honor Americans serving in the five U.S. military branches – the Army, Navy, Marines, Air Force, and Coast Guard – following the consolidation of the military services in the Department of Defense.
"It was intended to replace the separate Army, Navy, Air Force, Marine Corps, and Coast Guard Days, but the separate days are still observed, especially within the respective services.
"The first Armed Forces Day was celebrated by parades, open houses, receptions and air shows.
"In 1962, President Kennedy established Armed Forces Day as an official holiday.
"The United States' longest running city-sponsored Armed Forces Day Parade is held in Bremerton, Washington. In 2009, Bremerton celebrated the 61st Armed Forces Day Parade.
"Because of their unique training schedules, National Guard and Reserve units may celebrate Armed Forces Day/Week over any period in May. "
And now you know the 'rest of the story'.
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