On March 17, 1780, General George Washington granted the Continental Army a holiday “as an act of solidarity with the Irish in their fight for independence.”
On March 17, 1941, the U.S. Selective Service held its first lottery for the draft, in preparation for World War II. (Image, above, from the Morning Oregonian, from that year.)
Note that while the American Revolutionary War — also known as the American War of Independence — lasted less than nine years (1775–1783) and the global war known as World War II lasted less than seven years (1939–1945), with even less time for American involvement, the current War in Afghanistan looks like it may very well drag on over two decades. It is one of the longest active-fighting wars in world history.
Starting on October 7, 2001, the war has already garnered two separate code names, Operation Enduring Freedom – Afghanistan (2001–2014) and Operation Freedom’s Sentinel (2015–present).