When just a week ago Barack Obama showed a bit of ankle and declared the mere possibility of his running for the presidency, the chattering classes swooned. Now that every columnist in the country has given him advice, here's mine: He should run in '08. He will lose in '08. And the loss will put him irrevocably on a path to the presidency.

Obama's political challenge is to turn his current fame and sizzle, which will undoubtedly dissipate, into something concrete. In physics, it's the problem of converting kinetic energy into potential energy: Use the rocket fuel behind his current popularity to propel him to a higher national plane from which he would eventually move almost laterally to the presidency.

The reasons for running are clear.

First, at a time of ideological weariness, he has the persona: an affecting personal history, fine intelligence, remarkable articulateness and refreshing charm.

Second, this is a uniquely open race. Not since 1952 has there been a presidential election with no incumbent president or vice president running. Right now, there is no serious challenger to Hillary Clinton for the Democratic nomination. The Democrats' quadrennial great white hope -- the young attractive Southern governor in the mode of Jimmy Carter and Bill Clinton -- was going to be Mark Warner, former governor of Virginia. Warner has bowed out.

Third, the country hungers for a black president. Not all the country, but enough that, on balance, race would be an asset. It is no accident that when, a decade ago, another attractive, articulate African-American with no experience in electoral office went on a book tour, he was met not just with rock star adulation but with a loud national chorus urging him to run for the presidency.

The object of affection then was Colin Powell. Today it is Obama. Race is only one element in their popularity, but an important one. A historic one. Like many Americans, I long to see an African-American ascend to the presidency. It would be an event of profound significance, a great milestone in the unfolding story of African-Americans achieving their rightful, long-delayed place in American life.

Of course there is racism in America. Call me naive, but I believe that just as Joe Lieberman was a net positive for the Democrats in 2000 -- more people were attracted to him as a man of faith than were turned away because of anti-Semitism -- there are more Americans who would take special pride in a black president than are those who would reject one because of racism. Continued...