The importance of the Army-Navy football rivalry never needs stressed to those on the field and is rarely questioned by those off it. But on Dec. 1, 2001, in Philadelphia, less than three months after terrorists attacked U.S. soil and less than two months after the U.S. invaded Afghanistan, the game’s symbolic link to service and sacrifice resonated in a very real, very immediate way. In the postgame photo above, Army’s Brent Dial (21) and Navy’s Ed Malinowski (10), Chris Wade (43) and Chandler Sims (6) stand united. Dial shows none of the happiness one would expect after a 26-17…