In theory, and under the Constitution, the power to declare war rests with Congress. In practice, the president can take America to war without lawmakers’ consent. The War Powers Resolution of 1973 was supposed to act as a further check on the commander in chief. It hasn’t worked out that way, with at least three presidents ignoring a rule to give Congress 48 hours’ notice before committing troops. With Memorial Day a reminder of how such decisions can lead to the ultimate sacrifice, should the United States change the way it decides on going to war?