Have you ever wondered why phrases such as "sectarian violence," "ethnic cleansing" and "genocide" are heard so often around the world -- but not in the United States?

Why do people in so many other countries systematically slaughter their countrymen? And why is America a happy exception?

There are "killing fields" around the world, in Africa, the Middle East and Asia. But not here. One reason we are no longer cursed with civil strife is that Martin Luther King Jr. helped lift us above such brutality. So while his life and sacrificial death -- he was assassinated on April 4, 1968 -- are worth remembering, it’s even more important to remember his guiding principle: the peaceful resolution of disputes.

Growing up in the segregated South, King knew all about America’s history of violence, starting with the Indians and continuing with slavery and Jim Crow.

Yet, in his struggle for political change, King chose a different path: nonviolence. As a Christian, he aspired to the turn-the-other-cheek example of his savior. But, in addition, he could see that violence would only beget more violence. It was time to try a different approach.

As King put it in his speech accepting the 1964 Nobel Peace Prize, "Nonviolence is the answer to the crucial political and moral question of our time -- the need for man to overcome oppression and violence without resorting to violence and oppression."

And in the United States, at least, political action bore him out: The Civil Rights Act of 1964, the Voting Rights Act of 1965 and the Fair Housing Act of 1968 wrought a remarkably peaceful transformation of the South and of America.

On the day before his death, King was in Memphis, Tenn., providing moral support to striking sanitation workers and a related boycott against discriminatory employers. In describing the essence of "a relevant ministry," the civil rights crusader said, "It’s all right to talk about ‘streets flowing with milk and honey,’ but God has commanded us to be concerned about the slums down here, and his children who can’t eat three square meals a day."

Continuing in his legendary cadences, he added, "It’s all right to talk about ‘the new Jerusalem,’ but one day God’s preachers must talk about the new New York, the new Atlanta, the new Philadelphia, the new Los Angeles, the new Memphis."

And in that same speech, King preached yet again the importance of nonviolence. He even emphasized civility in the civil rights movement: "We don’t have to curse and go around acting bad with our words. We don’t need any bricks and bottles, we don’t need any Molotov cocktails."

Instead of weapons, he continued, his followers would bear the message of the cross: "We just need to go around to these stores, and to these massive industries in our country, and say, ‘God sent us by here, to say to you that you’re not treating his children right. And we’ve come by here to ask you to make the first item on your agenda fair treatment, where God’s children are concerned.’"

King was shot and killed the next day. And although a terrible spasm of riotous violence erupted after his assassination, over the past four decades, for the most part, the work of racial harmonization has continued. Yes, racism persists, and, yes, new cultural pathologies have emerged, but America is united and at peace with itself.

And the King legacy continues to find new expression -- most recently, in the candidacy of Sen. Barack Obama (D-Ill.). In his own mixed-race person, and in his determinedly gentle and optimistic persona, Obama epitomizes the sort of reconciliation that King dreamed of.

In the living spirit of Martin Luther King Jr., our country finds an enduring inspiration. Here in America, "sectarian violence" finds no home. And in this time of Passover and Easter, that’s something to be thankful for.