And it left the new president with a difficult choice. If he failed to use his office to criticize Harvard, Mr. Obama would anger black and liberal students; by speaking out, he would risk dragging himself and the review into the center of shrill debates.

People had a way of hearing what they wanted in Mr. Obama’s words. Earlier, after a long, tortured discussion about whether it was better to be called “black” or “African-American,” Mr. Obama dismissed the question, saying semantics did not matter as much as real-life issues, recalled Cassandra Butts, still a close friend. According to Mr. Ogletree, students on each side of the debate thought he was endorsing their side. “Everyone was nodding, Oh, he agrees with me,” he said.

As the president of the review, Mr. Obama once again walked a delicate line. He served on the board of the Black Law Students Association, often speaking passionately about the tempest of the week, but in a way that white classmates say made them feel reassured rather than defensive. He distanced himself from bombast; he did a mischievous impersonation of the Rev. Jesse Jackson when he came to speak on campus, recalled Franklin Amanat, now a federal prosecutor in Brooklyn. Mr. Obama’s boldest moment came at a rally for faculty diversity, where he compared Professor Bell to Rosa Parks.

But mainly, Mr. Obama stayed away from the extremes of campus debate, often choosing safe topics for his speeches. At the black law students’ annual conference, he exhorted students to remember the obligations that came with their privileged education. His speeches, delivered in the oratorical manner of a Baptist minister, were more memorable for style than substance, Mr. Mack said.

“It’s the inspiration of the speech rather than the specific content,” he said.

Just as he does now that he is a senator, Mr. Obama spoke then about his own biography — initially, Mr. Ogletree said, to correct anyone who assumed he had acquired his position with ease. His message, Mr. Ogletree said, was, “Don’t look at my success and assume that I have had a silver spoon in my mouth and gold coins in my hand.”

During the constant arguments about race and merit, everyone could point to Mr. Obama and find justification for their views. He had acknowledged benefiting from affirmative action in the past, so those who supported it saw him as the happy product of their beliefs.

But those who opposed it saw his presidency as the triumph of meritocracy. He was a black man who had helped one of Harvard’s most celebrated professors, Laurence H. Tribe, with an article on law and physics, and would graduate magna cum laude.