The national protests seeking an end to systemic discrimination against black Americans have given new fuel to a racial reckoning in economics, a discipline dominated by white men despite decades of efforts to open greater opportunity for women and nonwhite men.

A growing chorus of economists is seeking to dislodge the editor of a top academic publication, the University of Chicago economist Harald Uhlig, after he criticized the Black Lives Matter organization on Twitter and equated its members with “flat earthers” over their embrace of calls to defund police departments.

Days earlier, the profession’s de facto governing body, the American Economic Association, sent a letter to its members supporting protesters and saying that “we have only begun to understand racism and its impact on our profession and our discipline.” A group of economists, mostly from outside academia, last week hosted an online fund-raising effort for the Sadie Collective, an organization that aims to bring more black women into the field.

Black economists say the events have brought some progress to a field that has long struggled with discrimination in its ranks — and with a refusal by many of its leaders to acknowledge discrimination in the country at large. But the profession remains nowhere close to a full-scale shift on racial issues: On Wednesday, the director of the White House National Economic Council, Larry Kudlow, told reporters, “I don’t believe there is systemic racism in the U.S.”

Black Americans are vastly underrepresented among economics students and professors, a wide range of data have shown. There are no black editors of the most prestigious economics journals. There are no black professors in the main economics department at Chicago, Mr. Uhlig’s employer, which is one of the most storied departments in the country.

In a survey of economists released by the American Economic Association last year, only 14 percent of black economists agreed with the statement that “people of my race/ethnicity are respected within the field.”

As protests against discrimination have grown in recent days, a conversation has erupted — often led by black economists — over how the lack of diversity has left the profession ill equipped for a moment where policymakers are seeking ideas on how to combat racial inequality in policing, employment and other areas.

“Hopefully, this moment will cause economists to reflect and rethink how we study racial disparities,” the Howard University economist William Spriggs wrote to colleagues in an open letter that was posted this week on the website of the Federal Reserve Bank of Minneapolis.

“Trapped in the dominant conversation, far too often African American economists find themselves having to prove that African Americans are equal,” he continued. “We find ourselves, as so often happens in these ugly police cases, having to prove that acts of discrimination are exactly that — discrimination.”

Mr. Uhlig’s Twitter posts criticized demonstrators for not coordinating recent protests with law enforcement, before singling out Black Lives Matter over calls to defund the police.

“Look: I understand, that some out there still wish to go and protest and say #defundpolice and all kinds of stuff, while you are still young and responsibility does not matter,” Mr. Uhlig wrote. “Enjoy! Express yourself! Just don’t break anything, ok? And be back by 8 pm.”

The posts drew a swift backlash, including criticism from several white colleagues at Chicago and a petition calling for him to resign his editorship of the Journal of Political Economy, considered one of five journals with an outsize role in the field.

Mr. Uhlig, a 59-year-old German citizen, also faced scrutiny over past writings on his blog — circulated on Twitter by the Slate journalist Jordan Weissmann — that criticize black protesters in the United States.

Those included a 2017 post in which he asked supporters of National Football League players kneeling to protest police brutality, “Would you defend football players waving the confederate flag and dressing in Ku Klux Klan garb during the playing of the national anthem?” Mr. Uhlig also wrote a letter to the editor of The New York Times in 2016, complaining about calls for greater diversity in the motion picture industry at the Academy Awards.

“This whole ‘diversity = more American blacks in Hollywood movies’ thing?” he wrote. “So so strange. Really.”

Janet L. Yellen, the former Federal Reserve chair, said in an email on Wednesday that “the tweets and blog posts by Harald Uhlig are extremely troubling” and that “it would be appropriate for the University of Chicago, which is the publisher of the Journal of Political Economy, to review Uhlig’s performance and suitability to continue as editor.”

Mr. Uhlig apologized on Tuesday evening for his Twitter posts. He said in an email interview on Tuesday night that his “flat earther” comparison “appears to have caused irritation” but disagreed with critics who say his comments “hurt and marginalize people of color and their allies in the economics profession; call into question his impartiality in assessing academic work on this and related topics; and damage the standing of the economics discipline in society.” The reference to the Klan, he said, was a case where “I chose an extreme example” to make a point about free speech.

“Discrimination and racism is wrong,” Mr. Uhlig wrote in an email. Later, he added: “I would love to have more black economists (or is it ‘Afro-American economists’?) among our undergraduate students, Ph.D. students and faculty. It is my impression that the good ones are highly sought after. We also have very few American Indians among our colleagues. We need to find good way to change these numbers.”

Some conservatives hailed Mr. Uhlig as a champion of free speech and a victim of “cancel culture” — although critics said they were not seeking his dismissal from his tenured professorship.

Critics, however, held up Mr. Uhlig as an example of the deeply embedded advantages of white economists, including nearly full control over the journals that determine, in their selections for publication, which economists receive acclaim, tenure and top jobs.

“This is a way in which potentially good ideas, potentially good contributors of ideas to the economics profession, have been thwarted because of a gatekeeper,” Lisa Cook, a Michigan State University economist and one of the profession’s few prominent black women, said in an interview.

Ms. Cook leads the American Economic Association’s Summer Training Program, a decades-old effort to recruit black and Latino students to the profession. She said students often asked her how she overcame discrimination in the field, and whether they would be welcome.

“They’re asking where does this racially hostile environment come from?” she said. “Why does this racial discrimination exist in the pinnacle of the social sciences?”

Economics has a history of discrimination and, in some cases, outright racism. George Stigler, a Nobel laureate and an early leader of the American Economic Association, criticized the civil rights movement in 1962 and wrote that African-Americans’ disadvantages in the labor market stemmed in part from their “inferiority as a worker.”

“Lacking education, lacking a tenacity of purpose, lacking a willingness to work hard, he will not be an object of employers’ competition,” he wrote.

Few scholars today would use such language. But the ideas persist: Economics journals are still filled with papers that emphasize differences in education, upbringing or even IQ rather than discrimination or structural barriers.

Damon Jones, an economist at the University of Chicago’s Harris School of Public Policy, says the lack of diversity in economics affects what is studied and how. “We study things that are related to race and racism all the time, but we are inclined to figure out what other explanations may be at play,” he said.