When James K. Polk got his declaration of war as Mexico had "shed American blood upon the American soil," Rep. Abraham Lincoln demanded to know the exact spot where it had happened.
And did the Spanish really blow up the battleship Maine in Havana Harbor, the casus belli for the Spanish-American War?
The Gulf of Tonkin Incident, involving U.S. destroyers Maddox and C. Turner Joy, remains in dispute. But charges that North Vietnamese patrol boats had attacked U.S. warships on the high seas led to the 1964 resolution authorizing the war in Vietnam.
In 2003, Americans were stampeded into backing an invasion of Iraq because Saddam Hussein had allegedly been complicit in 9/11, had weapons of mass destruction and was able to douse our East Coast with anthrax.