Martin Luther King

Moreover, King was a man of extraordinary physical courage whose belief in nonviolence never swerved. From the time he assumed leadership of the Montgomery, Ala., bus boycott in 1955 to his murder 13 years later, he faced hundreds of death threats. His home in Montgomery was bombed, with his wife and young children inside. He was hounded by J. Edgar Hoover's FBI, which bugged his telephone and hotel rooms, circulated salacious gossip about him and even tried to force him into committing suicide after he won the Nobel Peace Prize in 1964. As King told the story, the defining moment of his life came during the early days of the bus boycott. A threatening telephone call at midnight alarmed him: "Nigger, we are tired of you and your mess now. And if you aren't out of this town in three days, we're going to blow your brains out and blow up your house." Shaken, King went to the kitchen to pray. "I could hear an inner voice saying to me, 'Martin Luther, stand up for righteousness. Stand up for justice. Stand up for truth. And lo I will be with you, even until the end of the world.'"

In recent years, however, King's most quoted line--"I have a dream that my four little children will one day live in a nation where they will not be judged by the color of their skin but by the content of their character"--has been put to uses he would never have endorsed. It has become the slogan for opponents of affirmative action like California's Ward Connerly, who insist, incredibly, that had King lived he would have been marching alongside them. Connerly even chose King's birthday last year to announce the creation of his nationwide crusade against "racial preferences."

Such would-be kidnappers of King's legacy have chosen a highly selective interpretation of his message. They have filtered out his radicalism and sense of urgency. That most famous speech was studded with demands. "We have come to our nation's capital to cash a check," King admonished. "When the architects of our Republic wrote the magnificent words of the Constitution and the Declaration of Independence, they were signing a promissory note to which every American was to fall heir," King said. "Instead of honoring this sacred obligation, America has given the Negro people a bad check; a check which has come back marked 'insufficient funds.'" These were not the words of a cardboard saint advocating a Hallmark card-style version of brotherhood. They were the stinging phrases of a prophet, a man demanding justice not just in the hereafter, but in the here and now.

TIME national correspondent Jack E. White has covered civil rights issues for 30 years

What If King Had Lived?
By Philip E. Tetlock

Dr. King's assassination in Memphis, Tenn., triggered riots in inner cities across the country and assured his place as a martyr for the civil rights movement. But what might have happened, both to King and to the movement he led, had he not chosen to walk out on the motel balcony that night and lived to march again? Such questions are hard to answer, but they are not unanswerable. History, after all, is about not only what happened but also what, for a few small turns of events, might have happened. Indeed, what didn't happen serves to underline the significance of what did. Such ruminations are the purview of counterfactual history, the examination of alternative outcomes based on plausible historical scenarios. To help distinguish frivolous flights of imagination from penetrating insights, counterfactual historians employ two standards:

THE MINIMAL-REWRITE RULE
A good counterfactual exercise tampers with as little of actual history as possible but still manages to get a big bang from what is changed. For example, as a foot soldier, Corporal Hitler had close brushes with death in World War I. Had this still unknown soldier been killed in action (with bullets whizzing all around him, it was a highly plausible possibility), humanity might have escaped World War II.

THE SO-WHAT TEST
An effective counterfactual scenario should checkmate critics who argue that things would have worked out the same way anyway (e.g., if Hitler had perished in the muddy trenches, some other fanatic would have taken his place. Maybe, but most historians see Hitler as an extremist, even for a Nazi--and one with a lot of charisma to boot). Counterfactualists tend to support the Great Man Theory of history.

Most of us normally do not think of small causes determining huge outcomes, such as millions dying because of a tiny but timely intervention. But maybe that just shows we are not thinking about our shared past in the right way. What-if thought experiments awaken us to the impact of chance and choice in history. There are endless games one can play with counterfactual history, but here are three deadly serious scenarios, each centered on a small event that turned out to have massive effects.