Martin Luther King Jr. is honored today for fighting (and dying) to unite a nation once divided by race.

There is much to appreciate about Dr. King's sacrifice. Thirty-nine years after his assassination, we're tempted to genuflect reflexively without considering what his sacrifice meant.

The improvement in race relations and the repudiation of legal discrimination has been so profound, we take it for granted as if it were an inevitable part of our political evolution. But those who remember the demoralizing sting of Jim Crow know that racial equality in this country was anything but a sure thing.

It took a long, hard-fought series of battles from the end of the American Civil War to the middle of the last century to get civil-rights legislation with teeth passed by Congress and signed by the president. Even so, we still haven't arrived at the Promised Land that Dr. King so eloquently cried out for in his famous sermon.

Even though racial reconciliation couldn't be legislated, Dr. King was determined to adhere, as much as possible, to a gospel of love and forgiveness. He taught others to do so as well.

In retrospect, his vision seemed like an impossible ethic to follow during the rising tumult of the 1960s. Narrowly defined identity politics and the growing radicalism of "black power" advocates conspired to dilute the moral force of the civil rights movement.

In an attempt to be more comprehensive in his critique of America's shortcomings, Dr. King turned his attention to the Vietnam War, the insidious effects of class and the need to restructure the economy so that no one was left behind.

His shift in focus alienated many of his supporters, both black and white. Dr. King was on the downward curve of his popularity the day he was murdered in April 1968.

Today as we look back on his life, it's important to honor everything Dr. King stood for -- not just the speeches that have sentimental value for us.

Martin Luther King Jr. was a complicated man. He was not a saint. He was an American who fought to have the Constitution and the laws of this land apply equally to all. That was a revolutionary sentiment at the time. His greatest legacy is that it doesn't sound so radical anymore.