Barack Obama has closed the deal among Democrats and will now be nominated for president. Young, eloquent, smart as a majority whip, his strengths — freshness, optimism — also give rise to concerns. Because of his slim track record, people are left to play hunches and look for clues as to how he would govern. Is he Kennedy-esque? Or more Kerry-esque? Is he an elitist with a populist bent, or a man of the people who indulges in tony affectations?

In the big campaign this fall, his personality is bound to come more into round, for better or worse.

For now, one of the things that cannot be overstated is just what a monumental moment this is for America. Being the first at anything is always a feather in one's cap, but being the first black person to be nominated by a major party puts Obama in a league with just a handful of others. The name Jackie Robinson comes to mind. Rosa Parks. Singer Marian Anderson, W.E.B. DuBois, co-founder of the NAACP, and Justice Thurgood Marshall are on that list.

And with every name on that list, Americans — of all shades — asked themselves: "Why has this taken so long? Are we really that blind?"

They are asking themselves that now about Obama.

Just as with Jackie Robinson and baseball, when the "color line" was broken, the floodgates opened up. Others streamed in.

Try to imagine American music, athletics, literature and religion without the presence of blacks. In many ways, the contributions of blacks have made those endeavors American.

So, now, with candidates for the presidency.

When Dr. Martin Luther King Jr. sang "We Shall Overcome," he undoubtedly included in his thoughts the invisible barrier that kept black people from the seats of power. Overcoming was about gaining clout. And when it comes to clout, there's no bigger stick in the world than one held by the president of the United States.

Obama's accomplishment will be appreciated more in the decades to come when historians mark watershed moments in American life. Yet, win or lose in November, he has already secured his legacy as an American icon — right up there with Louis Armstrong, Jesse Owens and Sojourner Truth.