Today is "the" Army's birthday, and that causes me a little heartburn.
When I was in "the" Army I had, like many Americans, completely confused the military history of our land forces with the history of "the" Army. They are not the same and Army historians will not let you forget it. I thought that the history of our Army encompassed and subsumed all previous and concurrent military organizations: militias, volunteers, Royal American regiments, National Guard, etc. Not at all.
And while historians may fight to have the Regulars recognized in the Civil War, the Regulars have had their revenge in spades ever since.
Today is the anniversary of the founding of the Continentals. Exclusively. No one's going to be raising a toast to your militia ancestor or your USV great grandfather. Believe me, I once tried it in "the" Army.