I personally know several people who have done this for the US Airforce Academy, and know of several others who have done it with West Point.
Of of my best friends told the Academy that he was leaving. They asked him why, and he said "mission".
They told him there won't be a guaranteed spot for him, until they found out he was learning Cantonese, and would come back a fluent speaker. At that point they promised him a spot to return to before he ever left.
Well, then I've no other choice than to say "it":
Never would 'ave happened in The Old Corps!