What if King had lived?

The preacher in him would have continued speaking out against injustice, war and maybe even pop culture. He would likely not have run for president. He probably would have endured more harassment from J. Edgar Hoover.

Four decades after the Rev. Martin Luther King Jr. fell to an assassin's bullet, colleagues and biographers offer many answers to the question: What if he had lived?

For his children, however, the speculation is more personal. They know their lives would have turned out differently had they had their father to guide and teach them.

Instead, history moves on, remaking the world in myriad ways. The nation has grappled with issues of race and inequity without the benefit of King's wisdom. A generation has come of age celebrating him in a national holiday, like other figures of the frozen past.

But given the trajectory of his life — from his appearance on the national scene during the Montgomery, Ala., bus boycott of 1955 to his death on a second-floor balcony of the Lorraine Motel in Memphis, Tenn., on April 4, 1968 — some of those closest to him have a good idea what King might be doing now, and where we might be as a country.

In the months before his death, King was speaking out against the growing U.S. involvement in Vietnam and was working with other civil rights leaders on a Poor People's Campaign, with a march on Washington scheduled for that May. He was in Memphis that spring day to support striking sanitation workers.

Were King alive today, the disciple of Mahatma Gandhi would most certainly be speaking out against the Iraq war, says King biographer David J. Garrow. However, citing the famous "Drum Major Instinct" sermon King delivered from the pulpit of Ebenezer Baptist Church in Atlanta just two months before his death, Garrow says people might be surprised to hear echoes of presidential candidate Barack Obama's controversial former pastor.

"God didn't call America to engage in a senseless, unjust war," King said of the fighting in Vietnam. "And we are criminals in that war. We've committed more war crimes almost than any nation in the world, and I'm going to continue to say it."

While King didn't go as far as the Rev. Jeremiah Wright in suggesting that God "damn America," he predicted that the Almighty might punish this country for "our pride and our arrogance."

"And if you don't stop your reckless course," he imagined the deity admonishing, "I'll rise up and break the backbone of your power."

Garrow and others feel comfortable saying that King would not have sought elective office.