The President sends U.S. military forces into an area where they come under enemy fire. Congressmen denounce him for dragging the nation into battle "unconstitutionally." But it is too late; war has begun, and Congress has no choice except to let it continue.
A description of how the U.S. got into war in Viet Nam in 1965? Or how it might become embroiled in the Persian Gulf conflict the day after tomorrow? Not quite: this war began in 1846, when President James K. Polk sent troops to occupy a disputed border area between Mexico and the new state of Texas, touching...

