Article One, Section Eight of the Constitution says, "Congress shall have the power...to declare war." And yet, the United States has gone to war again and again without a formal congressional declaration of war. In fact the last time an American president asked Congress for a declaration was in 1941 — right after the attack on Pearl Harbor.
Since then, one president after another — from Harry Truman to Barack Obama, has ordered American troops into wars all over the world: from Korea to Vietnam, Panama and Grenada, to Lebanon, Bosnia, Afghanistan and Iraq. Some would argue that nuclear weapons and the advent of the United Nations have turned conflicts like these into international rather than unilateral efforts.
Marvin Kalb, veteran journalist, author of a new book: "The Road to War: Presidential Commitments Honored and Betrayed"
This segment aired on June 11, 2013.