The night Barack Obama won the election, the old common sense about race in America suddenly died. Now the United States is a place where a black man can become president. This new fact could spark a revolution, if the country asks how much more progress is possible.

One step is to look at affirmative action in light of Mr. Obama's victory.

Angry claims about affirmative action handouts and quota queens could give way to a simpler question: Who is missing out on the American dream, and what can be done about it? This wouldn't be about making up for past injustices. It would simply fulfill America's destiny as a land of opportunity.

Republicans often argue that education is the real civil rights issue of the 21st century. That's largely true. Greater public investment in early-education programs, K-12 schools, and public colleges could help more people thrive.

But even the best schools can't change society alone. The country has to help children and adults overcome severe disadvantages. Racism is one. But also poverty, incarceration, homelessness, drug addiction, physical abuse and mental illness.

The country must also accept its own changing face. Asked if his daughters should benefit from affirmative action, Mr. Obama reasonably said no, pointing out the obvious privileges that his children have. But the relevant question is not what America might do for the Obama girls, but what they could one day do for an increasingly diverse nation where by 2050 "minorities" will make up more than half of the population, according to Census Bureau predictions. This future America will need more police officers, medical researchers, software engineers and neighbors who can help build multicultural prosperity.

Time is running out -- at least legally. In 2003, then-Supreme Court Justice Sandra Day O'Connor set a clock ticking when she wrote the Grutter v. Bollinger ruling. The court defended the University of Michigan's "narrowly-tailored use of race" in its law school admissions process as a means of creating a diverse student body. The caveat: "The Court expects that 25 years from now, the use of racial preferences will no longer be necessary to further the interest approved today."

Five years later, not enough progress has been made. But there is at least the potential that the nation could spend the next 20 years moving away from stale notions of affirmative action and toward an unprecedented era of widespread opportunity.