Larry Summers was ousted as Harvard president. He has a lot to say about what’s wrong with the university now.

Summers was among the first to publicly attack Harvard for its silence after the Oct. 7 attacks on Israel, posting on X, “In nearly 50 years of @Harvard affiliation, I have never been as disillusioned and alienated as I am today.”

He was at the forefront of a stampede of criticism that prompted Harvard’s first Black president, Claudine Gay, to resign in January. Then, he swiftly panned her successor’s pick to help lead a task force on antisemitism, declaring he had “lost confidence” in Harvard.

A few weeks ago, echoing the arguments of conservative critics, Summers blamed the crisis in higher education on, in part, a preoccupation with diversity.

“We have stepped away from merit and excellence, and we have adopted a particular concept and set of concepts of social justice as being at the center of the purpose of universities,” Summers said in an interview on the podcast “The Good Fight with Yascha Mounk,” in late February.

Some of his critics wonder if there’s an element of personal pique at play. The same progressive forces that helped expel him from the presidency elevated Gay, whom Summers thought was not a strong candidate for president, based on her work as dean and on her scholarship. His views were well-known in the university community.

“Hopefully, Larry’s intentions are not about revenge but about making Harvard a better place,” said David A. Thomas, president of Morehouse College, who was a professor and administrator at Harvard Business School during Summers’ tenure as university president. “The way he’s going about it in the long term is ineffective, precisely because it looks like it’s sort of a moment for him to avenge his sense that he was somehow not treated well because he did have issues with women and the Black community.”

At Harvard, some of Summers’ colleagues say they’re shocked by his open attacks.

“Why somebody who spent his entire adult life at Harvard and had the honor of being president of Harvard . . . would try and take a wrecking ball to Harvard the way he has in recent months is beyond me,” said Steven Levitsky, a government professor at Harvard.

In an interview with the Globe, Summers dismissed the sense that he is avenging his ouster.

“I have long since moved on,” he said. “My focus for many years now has been on my teaching, my research, and my contributions to economic policy, not on the internal affairs of the university,” he added.

Summers said he is raising up “important issues of conscience,” which others in the community “have been afraid to speak out on.”

His primary and abiding concern, Summers said, is antisemitism on campus. After Hamas attacked Israel — and dozens of Harvard student groups issued a statement that appeared to justify the attacks and aligned themselves with Palestinians — Summers called out Harvard for “a double standard” of reacting zealously to prevent discrimination against some groups, but failing to protect Jews.

The university needs “to do much more to respond to antisemitism,” said Summers, who is Jewish, “in ways that are parallel with other forms of prejudice.”

University officials have acknowledged antisemitism is a growing problem at Harvard, but Summers wants more decisive action. In February, when an antisemitic cartoon was posted on social media by pro-Palestinian groups of students, faculty, and staff, Summers praised interim president Alan Garber for condemning that cartoon. But at the same time, in a 10-part tweet thread, he provocatively questioned whether faculty “who were party” to the statements would be asked to resign.

When Garber appointed the task force on antisemitism in January as part of his efforts to address tensions and concerns on campus, Summers joined some big donors in attacking Derek Penslar, a leading Jewish scholar Garber chose to cochair the group, saying he had “minimized Harvard’s anti-Semitism problem” and “referred to Israel as an apartheid state.” Penslar declined to comment for this story, but he has remained in the role after hundreds of Jewish leaders and scholars publicly vouched for his credentials.

From Summers’ perspective, the proponents of diversity, equity, and inclusion on college campuses who see the world as divided between the “oppressed” and “oppressors” — and view Israel as oppressing Palestinians — are to blame for growing antipathy toward the Jewish state.

Many Jewish alumni and students said they appreciate that someone of Summers’ stature is willing to speak out and serve as an ally, when they have felt ignored by the university’s administration.

“He gets the moment,” said Roni Brunn, a spokesperson for Harvard Jewish Alumni Alliance, which has been lobbying administrators to root out antisemitism on campus and is conducting a university-wide audit identifying sources of anti-Israel and anti-Jewish sentiment in course offerings. In early February, Summers spoke via Zoom to 350 members of the alliance about his Jewish identity and how Harvard can fight antisemitism, Brunn said.

“He has given us focus and given us hope,” Brunn said, “that what we want is completely normal.”

Some students who speak up for Palestinian rights, however, have found Summers’ advocacy problematic.

Violet Barron, a 19-year-old sophomore at Harvard College, called Summers’ public condemnation of student groups that speak up for Palestinians “an asymmetric leveraging of power, and that feels wrong.”

While Barron called it an “undeniable fact” antisemitism is growing nationally, she said the threat at Harvard has been overstated by Summers and others because so many conflate anti-Zionism with antisemitism. She was among those who founded the group Jews for Palestine at Harvard after Oct. 7 to “correct the narrative that had been so blown out of proportion.”

Summers did speak out last fall against the doxxing of pro-Palestinian students who signed a controversial letter following the attacks. “It is a time for absolute clarity that words or deeds that threaten the safety of others in our community will not be tolerated,” he tweeted. But he remains adamant the antisemitism on campus is, if anything, underestimated.

Known as a brilliant economist and a top economic adviser to the Clinton and Obama administrations whose guidance has been sought out by bankers, hedge fund managers, and more recently artificial intelligence pioneers, Summers has never been shy about offering his opinion, whether publicly or behind the scenes, at Harvard and other organizations with which he’s involved.

Jason Furman, who, like Summers, worked as a top national economic adviser and teaches in both Harvard’s economics department and the Kennedy School of Government, said Summers “just cares enormously,” and “thinks he makes things better by speaking his mind.”

Furman experienced Summers’ unvarnished critiques himself when he was the chairman of the Council of Economic Advisers, and sent regular updates to his email list of some 300 people.

“Larry would write back: ‘Here are 10 things you did wrong, three things you should think about, and two points you should have made but didn’t,’” Furman said.

Summers, who will turn 70 later this year, is famous for presenting his ideas with boundless certitude. He is not always right.

In the 1990s, while Summers was at the Treasury Department, he adamantly fought efforts to regulate complex financial derivatives, which many blamed for contributing to the 2008 economic crisis. More recently, as an economic commentator, he incorrectly predicted the aggressive interest rate increases by the Federal Reserve to bring inflation under control would lead to a recession and spike in unemployment.

These days, Summers still teaches three classes at Harvard in the fall and divides his time between Cambridge and Arizona, where his wife, also an academic, runs a center. He downplayed his stature as a president emeritus and national figure, suggesting he’s interjecting his ideas about Harvard as any professor might.

“I do not feel that the fact that many people listen to me constitutes a reason why I should not be allowed to express opinions,” he said.

Summers acknowledged he has made behind-the-scenes calls to influential players at Harvard, letting them know he was following their response to the turmoil on campus, and that he was prepared to publicly speak out about it.

Alison Frank Johnson, a Harvard history professor, said stories of faculty and administrators feeling bullied by Summers abound on campus, where she has taught since 2005. Frustrated Harvard faculty have in recent months even pleaded with Garber to intervene and ask Summers to dial back his public take-downs, she said. Garber, however, has stressed Summers has the freedom to say what he wants, she said.

“A tool that he uses in the bullying is the threat of public sort of shaming,” Frank Johnson said.

Summers dismissed the claim those private conversations amount to stifling free speech or threatening and bullying of his colleagues. In fact, Summers said, he views it as “a basic courtesy” to give the targets of his criticism advance notice.

“I don’t believe in going after people,” Summers said. “But academic freedom does not include freedom from criticism. And when I’m going to criticize views, I’ve tried always to give people notice in advance that I was going to do that.”

He acknowledged, however, that he did not alert Rashid Khalidi, a professor of modern Arab studies at Columbia University in New York City, before criticizing him on social media. In a late January post on X that drew 2.8 million views, Summers criticized Harvard for twice inviting Khalidi, “who many see as anti-semitic,” to speak on campus. Summers later tweeted that it was a mistake to link Khalidi to antisemitism, and that he had personally reached out to Khalidi.

Asked about the exchange, Khalidi said: “I have nothing to say about Larry Summers.”

Brian Rosenberg, former president of Macalester College in Minnesota and a visiting professor at the Harvard School of Graduate Education, said Summers’ recent critical commentary may have bolstered his image as an influential insider.

But has it helped students at Harvard? Probably not, Rosenberg said.

“My advice would be to be quiet,” Rosenberg said. “But I’m sure he would not take that advice.”

Stephanie Ebbert can be reached at Stephanie.Ebbert@globe.com. Follow her @StephanieEbbert. Deirdre Fernandes can be reached at deirdre.fernandes@globe.com. Follow her @fernandesglobe.