Forty years after the assassination of Dr. Martin Luther King Jr., it’s high time America did something to break the cycle of poverty that he railed against, the civil-rights leader’s eldest son said Friday.

“Forty years ago, my father was focused on the Poor People’s Campaign to guarantee an annual income for all citizens,” Martin Luther King III told TODAY’s Ann Curry. “Tragically, today, 40 years later, where 36 million people are living in poverty — 12 million children — we’re not doing near enough.”

King III was just 10 years old when his father was killed by a single shot to the head while standing on the balcony outside his Memphis motel room. Now 50, he has gone on to become an international human rights advocate and the founder and CEO of the nonprofit organization Realizing the Dream, formed in 2006 to promote conflict resolution, nonviolence training, youth leadership training and community and economic development.

In anticipation of the April 4 anniversary of his father’s death, King III had written an op-ed piece for the Atlanta Journal and Constitution calling on all three remaining presidential candidates — Republican John McCain and Democrats Hillary Clinton and Barack Obama — to commit to appointing a cabinet-level poverty czar within the first 100 days of his or her administration.

“We’ve got to focus on this issue,” he said, speaking in front of his father’s Ebenezer Baptist Church in Atlanta. “And it takes a person like a cabinet-level member, I believe, to address and galvanize the energy to effectively address poverty. If we can spend 30 billion to bail out Bear Stearns, then certainly we can find resources to address the issues of the masses of people in America.”

With King III was his sister, the Rev. Bernice King, the only one of the four King children to follow their father into the ministry. Just 5 when her father was killed, Bernice King struggled for years to understand why God allowed her father to be taken from her.

“My calling to the ministry has greatly answered the question,” she told Curry, who was reporting live from the Memphis motel — now a museum and historic site — where Dr. King was killed. “I now understand the sacrifice that our father made to change a nation and a world was a part of his calling into ministry. In Christian ministry, you believe you die to yourself so that you might serve humankind.”

Slide show   Martin Luther King Jr. See the civil rights leader in speeches and marches from Alabama to Washington. more photos

Dr. King was just 39 when he was killed by an assassin. He was a Nobel Peace Prize winner and the charismatic leader of a massive civil-rights movement, but he did not volunteer for that role. Rather, he was drafted into it in 1955 in Montgomery, Ala., where he was a brilliant young pastor when Rosa Parks refused to move to the back of a city bus as segregation laws required.

Parks’ simple act sparked a bus boycott and gave birth to the movement that ultimately brought down the Jim Crow laws, and Dr. King, a fervent believer in nonviolent protest as espoused by Gandhi, became the leader of that movement.

His signature moment was the “I Have a Dream” speech he gave to a multitude of a quarter of a million people in front of the Lincoln Memorial in Washington, D.C., in 1963. The speech galvanized a nation and led to the passage of the Civil Rights Act of 1964 and the Voting Rights Act of 1965.

By 1968, his campaign against pervasive poverty brought him to Memphis to speak in support of striking black sanitation workers. He had just dressed for dinner and stepped out on the balcony of his motel room when he was killed.

The assassination touched off a series of riots that swept through 125 American cities.

There were no major formal programs organized around the anniversary of Dr. King’s death until this, the 40^th anniversary. Friday afternoon in Memphis a march will proceed to the site of the assassination, where the moment of his death — 6:01 p.m. Central Time — will be marked.

The Rev. Al Sharpton, who will participate in the march, told TODAY’s Al Roker that it is time to renew Dr. King’s fight.

“Rather than just talk about what happened 40 years ago, we want to commit ourselves to continuing the work of fighting poverty, fighting racism, fighting militarism,” he said. “At the exact hour that Dr. King was shot, we will have a moment of recommitment.”

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