Saturday marks the 72nd anniversary of the attack on Pearl Harbor, and a day that President Franklin D. Roosevelt presciently predicted would "live in infamy."
At 12:30 p.m. on December 8, 1941 -- a day after Japanese planes launched a sneak attack on U.S. forces stationed in Hawaii, killing more than 2,400 soldiers and civilians and wounding over 1,000 more -- Roosevelt stood before a Joint Session of Congress and called for lawmakers to authorize a formal declaration of war against Japan. Within an hour of the speech above, the United States had officially entered World War II, the deadliest conflict in human history.
The U.S. hasn't officially declared war since, though it has been involved in numerous military engagements, often authorized without congressional approval. With the advancements in military technology and proliferation of nuclear weaponry since World War II, it seems highly unlikely that humankind -- or at least massive parts of it -- could survive another war of this size or scope.