When Martin Luther King was killed in Memphis I was a college student, active in the 1968 campaign for president, protesting the Vietnam War and engaged in civil rights. The fact that 40 years have gone by since that weekend does not make those events any less fresh in my mind.

I remember the American flag and the United Nations flag at Macalester College in St. Paul being lowered to half-mast and the prayers that were said as students gathered in front of the chapel. I remember the shock that another hero could be taken from us less than five years after John Kennedy was assassinated. I remember calling home to my family in Washington, D.C., who told me that they could see the smoke and fires from the downtown riots. And I remember the footage of Robert Kennedy in Indiana as he spoke to an African-American crowd who had not yet heard the news and his quoting Aeschylus: "Even in our sleep, pain which cannot forget falls drop by drop upon the heart, until, in our own despair, against our will, comes wisdom through the awful grace of God."

In our country, we have yet to find that wisdom, we still face barriers that are part of our culture, but we do find ourselves in the midst of a presidential campaign where a black man or a white woman stands a good chance of being elected to the highest office in the land, something unimaginable in 1968.

The next Martin Luther King anniversary, as Gary Hart told me the other day, will take place on Aug. 28, the day that the Democratic nominee will give the acceptance speech in Denver — the 45th anniversary of the “I Have a Dream” speech at the Lincoln Memorial in 1963.

Our country needs these reminders … and needs leaders like Martin Luther King and Robert Kennedy who were not afraid to put themselves into the arena and to speak courageously to transform our politics.