Attorney General Eric H. Holder speaks about the 60th anniversary of Brown v. Board of Education at the Morgan State University commencement. (Barbara Haddock Taylor/Baltimore Sun)

The Obama administration has entered an unexpected, unpredictable debate over the nation’s racial progress, warning in several events last week that much work remains to be done.

Nearly six years after the United States elected its first black president, the signposts of the latest discussion have appeared across the cultural landscape — from the professional sports arena, to the diminishing Western frontier, to a little New England town where an elected official is refusing to apologize for referring to the president by a famously derogatory racial epithet.

On Saturday, Attorney General Eric H. Holder Jr. provided the administration’s starkest assessment to date. In a commencement address, Holder warned that recent public episodes of racial bigotry should not obscure the greater damage done by more systemic forms of prejudice and discrimination.

“If we focus solely on these incidents — on outlandish statements that capture national attention and spark outrage on Facebook and Twitter — we are likely to miss the more hidden, and more troubling, reality behind the headlines,” Holder told the graduating class at Morgan State University in Baltimore.

Holder was alluding to recent firestorms such as those set off by Nevada rancher Cliven Bundy, who gained notoriety for an armed standoff with federal officials and then offered a critique of black people in which he suggested that they may have been better off as slaves, and by Los Angeles Clippers owner Donald Sterling.

Saturday, Holder warned against the spectacle of such episodes. “These outbursts of bigotry, while deplorable, are not the true markers of the struggle that still must be waged, or the work that still needs to be done,” Holder said.

“The greatest threats,” he continued, “are more subtle. They cut deeper. And their terrible impact endures long after the headlines have faded and obvious, ignorant expressions of hatred have been marginalized.”

These high-profile, racially charged controversies have coincided with what the administration, and many others, hoped would be a moment of celebration surrounding the 60th anniversary of the Supreme Court’s Brown v. Board of Education ruling, which ended — legally, at least — racial segregation in public education.

The timing has offered the administration, reluctant over the years to discuss race overtly, an opportunity to appraise the halting character of the country’s racial progress and those resisting its next steps.

The Morgan State comments were Holder’s most extensive on the subject of race since early 2009, when he gave a speech during Black History Month that generated controversy and reportedly infuriated President Obama’s chief of staff at the time, Rahm Emanuel. In that speech, Holder, the nation’s first African American attorney general, referred to the country as “essentially a nation of cowards,” arguing that Americans were not comfortable enough with one another to discuss the issue of race candidly.

The Saturday address — which aides said was vetted by the White House — was centered more squarely on the issues that have animated Holder in the twilight of his tenure, particularly criminal-sentencing policies and voter-identification laws.

Those issues have also interested Obama, who in his second term has made a more overt effort to address the problems of urban America and the African American community more broadly.

Obama has rarely — and reluctantly — involved himself directly in national moments of racial debate. His first foray as president turned into a politically awkward one when, in response to a reporter’s question, Obama said Cambridge, Mass., police “acted stupidly” in arresting Harvard professor Henry Louis Gates Jr., head of the university’s W.E.B. DuBois Institute for African and African American Research, at his home.

He later brought Gates and the arresting officer together at the White House for beer and conversation. But his support among white males, which dipped sharply at the time, has never fully recovered.

Last year, Obama directly addressed the raw feelings of African Americans after the acquittal of George Zimmerman, a member of a Florida neighborhood watch group, in the fatal shooting of 17-year-old Trayvon Martin in 2012.

He urged the country to “do some soul-searching” after the verdict, adding that “it’s important to recognize that the African American community is looking at this issue through a set of experiences and a history that doesn’t go away.”

But Obama has remained largely outside the current debate, set off by the Bundy remarks last month. He joked about them at the White House Correspondents’ Association dinner but has declined to address them seriously.

Soon after Bundy spoke, a recording of Sterling, the longtime owner of the National Basketball Association’s Clippers, was made public. Sterling was heard telling his girlfriend not to bring African Americans with her to Clippers games, prompting the NBA to begin legal proceedings to strip him of the team. Obama, through a spokesman, said he supported the move to ban Sterling from the league for life.

Then last week, news broke of Robert Copeland, a police commissioner in Wolfeboro, N.H., who admitted that he had referred to the president with a racial slur and then explained it this way, according to newspaper reports: “I believe I did use the ‘N’ word in reference to the current occupant of the Whitehouse [sic],” he wrote. “For this I do not apologize — he meets and exceeds my criteria for such.”

On Friday, in a private celebration of the anniversary of the Supreme Court’s desegregation ruling, Obama met with families of the plaintiffs in the Brown case at the White House.

“As we commemorate this historic anniversary, we recommit ourselves to the long struggle to stamp out bigotry and racism in all their forms,” Obama said in a statement. “We reaffirm our belief that all children deserve an education worthy of their promise. And we remember that change did not come overnight, that it took many years and a nationwide movement to fully realize the dream of civil rights for all of God’s children.”

First lady Michelle Obama spoke more publicly about the historic anniversary, traveling last week to Topeka, Kan., to mark the moment with a candid assessment. “So today, by some measures, our schools are as segregated as they were back when Dr. King gave his final speech,” she told a group of graduating seniors from across the Topeka School District. “As a result, many young people in America are going to school largely with kids who look just like them,” she continued. “And too often, those schools aren’t equal, especially ones attended by students of color which too often lag behind, with crumbling classrooms and less experienced teachers.”

Holder took up that message Saturday at Morgan State, a historically black college. In a pointed and at times personal speech, Holder argued that America’s struggle for racial equality has become defined less by expressions of outright bigotry than by policies that subtly but systematically impede equal opportunity.

In the case of the criminal-justice system, Holder pointed to “systemic and unwarranted racial disparities,” noting that a study last year by the U.S. Sentencing Commission found that in recent years African American men have received sentences that are nearly 20 percent longer than those imposed on white males convicted of similar crimes.

Another report showed that American Indians are often sentenced even more harshly, he said.

“Disparate outcomes are not only shameful and unacceptable,” Holder said, “they impede our ability to see that justice is done.”

Similarly, Holder said that voter-ID laws that have been enacted in a number of states threaten to make it harder for minorities to exercise their rights at the polls. Proponents of the measures say they are intended to combat voter fraud, a problem that Holder has dismissed as virtually nonexistent. “Rather than addressing a supposedly widespread problem, these policies disproportionately disenfranchise African Americans, Hispanics and other communities of color,” he said.

Holder also expressed concern about “zero tolerance” disciplinary practices at schools, saying that they are “well intentioned” but affect black males at three times the rate they affect their white peers.

Beyond policy issues, Holder spoke broadly about the struggle for racial equality and what he suggested was the failure of some to fully grasp the degree to which minority groups can be marginalized. He took direct aim at the Chief Justice John G. Roberts Jr., who famously wrote in a 2007 opinion that “the way to stop discrimination on the basis of race is to stop discriminating on the basis of race.”

“This presupposes that racial discrimination is at a sufficiently low ebb that it doesn’t need to be actively confronted,” Holder countered. “In its most obvious forms, it might be. But discrimination does not always come in the form of a hateful epithet or a Jim Crow-like statute. And so we must continue to take account of racial inequality, especially in its less obvious forms, and actively discuss ways to combat it.”