Supreme Court Justice Roger B. Taney, writing for the majority in the 1857 Dred Scott decision, described African Americans as "beings of an inferior order, and altogether unfit to associate with the white race either in social or political relations, and so far inferior that they had no rights which the white man was bound to respect."

Now, 151 years later, a black man has been elected president of the United States. Even the most pessimistic of pessimists have grudgingly conceded that Barack Obama's election represents a seminal moment in American history.

Because of Obama's victory over John McCain, Americans are more optimistic than ever about the future of race relations. A USA Today/Gallup Poll taken the day after the election found that two-thirds of Americans said they felt "proud" and "optimistic" after Obama's victory. Six in 10 said they were "excited."

But before we dislocate an elbow patting ourselves on the back, we need to examine the figures more closely. There is both good news and bad news in the election returns.

The bad news is that, if only whites had voted on Election Day, John McCain would be president-elect. Even in the battleground states that Obama swept - Pennsylvania, Ohio, Virginia, Florida and Indiana - McCain out-polled Obama among whites.

The good news is that, while Obama did not win a majority of the white vote, he won 43 percent of it - two percentage points more than John Kerry's share four years ago. In states outside the South, Obama won more white votes than any Democratic nominee since Lyndon B. Johnson's landslide in 1964, according to an analysis by David A. Bositis, senior research associate at the Joint Center for Political and Economic Studies.

We're a long way from the Dred Scott decision, which proclaimed that people of African descent could not be U.S. citizens. That decision was officially overturned with the passage of the 13th Amendment abolishing slavery in 1865 and the 14th Amendment guaranteeing full rights and citizenship regardless of race in 1868. It wasn't until 1965 that the Voting Rights Act allowed African Americans to vote without fear.

Race has always been America's Achilles' heel. It has never been easy to square the Founding Fathers' quest for liberty with their ownership of slaves.

The Declaration of Independence declared: "We hold these truths to be self-evident, that all men are created equal, that they are endowed by their creator with certain unalienable rights, that among these are life, liberty and the pursuit of happiness." However, "all men" did not include black men. Nor did it include women.

Neither women nor the descendants of Africans could hold public office, serve on juries, or bring lawsuits for much of our history. Women were not even allowed to serve as legal guardians of their own children.

Over time, prodded by abolitionists and civil-rights activists, the nation changed. America is far more diverse now than ever before. Minorities make up about a third of the population, and they will constitute a majority by 2042.

This will put increasing pressure on different groups to get along better. As former New Jersey Sen. Bill Bradley observed, "Slavery was America's original sin, and racism remains its unresolved dilemma."

The problem extended far beyond slavery. Jim Crow laws mandating separate facilities for blacks and whites did not end until the mid-1960s. Even today, racial discrimination pervades American society.

Sure, America has elected its first African American president. But that does not automatically remove discrimination and prejudice from our society. Racial profiling is still an issue in many cities.

Advocacy groups have shown that whites are still more likely to get an apartment than their black counterparts. We learned during the mortgage meltdown that credit-worthy blacks with well-paying jobs were often steered toward subprime loans.

In his Philadelphia speech on race, Obama observed: "This is where we are right now. It's a racial stalemate we've been stuck in for years. Contrary to the claims of some of my critics, black and white, I have never been so naïve as to believe that we can get beyond our racial divisions in a single election cycle, or with a single candidacy - particularly a candidacy as imperfect as my own."

Still, the election of Barack Obama may help us move beyond racial divisions. Vernon Jordan, the former National Urban League president and adviser to Bill Clinton, put it best: "We may have come over on different ships, but we're in the same boat now."