MIAMI — Of the many student activists who emerged from the tragic shooting in 2018 at Marjory Stoneman Douglas High School in Parkland, Florida, Kyle Kashuv stood out as a conservative defender of the Second Amendment, surrounded by classmates who were mobilizing for sweeping new controls on guns.

He used that distinction to get meetings with the likes of President Donald Trump and successfully push for what he believed would be more effective federal legislation to improve school security and help detect potential threats of violence at schools, as he proudly related in his admission essay to Harvard College.

In the essay, he described hiding in a classroom closet during the February 2018 rampage in which 17 people were killed. He said he learned about the deaths of his classmates one by one and chose to devote himself to activism afterward.

“While I support a conservative viewpoint on the Second Amendment, I know that finding common ground is the path to protecting our students,” he wrote. “I still believe that from the pits of despair, goodness can and will prevail.”

Harvard accepted him into its freshman class — briefly.

On Monday, Kashuv revealed on Twitter that the university this month rescinded its admission offer over a trail of derogatory and racist screeds that it turns out Kashuv, 18, wrote as a 16-year-old student, months before the shooting that would turn his high school into one of the most famous in the country.

Kashuv, who had apologized for the comments when they became public in May, did so again Monday as he announced Harvard’s decision on Twitter. It followed, he said, a campaign against him organized by political opponents and former classmates who long ago stopped being his friends.

“Hopefully people have the goodness in their hearts to forgive me,” Kashuv said in a telephone interview. “I really hope that. What I said two years ago isn’t indicative of who I am.”

Some conservatives decried Harvard’s decision as unfair, once again thrusting the fraught issue of college admissions into the public eye. And the rescinded offer raised a question uniquely relevant to the digital age: To what degree should the pronouncements of young people who routinely document their thoughts online — in this case, in a private study document shared with a few classmates — follow them into adulthood?

A Harvard spokesman declined to comment, citing college policy on discussing an individual applicant’s admission status. In 2017, the college rescinded admission offers for at least 10 applicants who had shared sexually explicit and other offensive memes and messages in a private Facebook group.

Harvard informs students upon their admission that the college reserves the right to withdraw its offer for several reasons, including if an admitted student “engages or has engaged in behavior that brings into question their honesty, maturity or moral character.”

William Fitzsimmons, dean of admissions and financial aid, cited “maturity and moral character” in informing Kashuv of the rescinded admission offer.

“After careful consideration the committee voted to rescind your admission to Harvard College,” Fitzsimmons wrote in a letter dated June 3, which Kashuv shared on Twitter. “We are sorry about the circumstances that have led us to withdraw your admission, and we wish you success in your future academic endeavors and beyond.”

Instead of taking a gap year and matriculating at Harvard in the fall of 2020 as he planned to do, Kashuv said he now expects he will have to reapply to colleges, since it is too late to accept admission offers from other schools that had offered him scholarships.

Two other prominent Parkland student activists, Jaclyn Corin and David Hogg, both of them vocal proponents of tighter gun restrictions, are headed to Harvard this fall. Hogg, who is completing a gap year, garnered attention when he announced his acceptance last year after being rejected from other schools, including from California State University at Long Beach. On Monday, Kashuv’s defenders noted that Hogg had a 4.2 GPA and scored 1270 on the SAT test, while Kashuv said in the interview that he had a 5.4 GPA and a 1550 SAT score.

Unlike some of his classmates who became national figures after starting a youth movement against gun violence, Kashuv garnered widespread attention as a young voice in favor of gun rights. In Washington, he lobbied in support of the STOP School Violence Act and a law stepping up requirements for reporting on criminal background checks on gun buyers; both passed in 2018.

He served as the high school outreach director for Turning Point USA, a conservative group with ties to the Trump family. Kashuv has since stepped down from that position, though he said Monday his departure was unrelated to the comments that got him into trouble with Harvard.

A video showing screenshots of what he wrote, including repeated racial slurs, was posted online in May by a former schoolmate. The screenshots show that Kashuv and other students used a Google Doc study guide as a chat, with several of them editing the document simultaneously and commenting on each other’s remarks. In laying out the story Monday morning to his 304,000 Twitter followers, Kashuv said the “egregious and callous” comments were made “in an attempt to be as extreme and shocking as possible,” not because of any personal beliefs.

One screenshot shows Kashuv using a racial slur for African-Americans more than a dozen times.

“like im really good at typing” the slur, he wrote. “ok like practice uhhhhhh makes perfect son??!!”

In a different screenshot of a text message, Kashuv also used the slur to refer to black student athletes.

Ariana Ali, the former schoolmate who posted video of the messages on Twitter, declined to elaborate Monday beyond praising Harvard’s rescinding of Kashuv’s admission offer.

“He’s being held accountable, & I think the consequences were necessary,” she said in a direct message on Twitter.

Ali’s video drew attention from several news outlets and Kashuv’s critics, including a far-right activist, Laura Loomer. Six days later, Kashuv resigned from Turning Point USA and issued a statement regretting his past comments. Two days later, Harvard inquired about the reports and asked Kashuv for an explanation.

Kashuv told Harvard he apologized “unequivocally.” He said he could not recall what he had written beyond what his former classmate had made public and had no record of the conversations himself.

“My intent was never to hurt anyone,” Kashuv wrote to the college. “I also feel I am no longer the same person, especially in the aftermath of the Parkland shooting and all that has transpired since.”

The Google Doc comments were made late at night as the students tried to outdo each other with outrageous remarks, Kashuv said Monday, describing himself as thoughtless and immature at the time.

“In the same document, I said a bunch of anti-Semitic stuff,” he acknowledged. “That’s not who I am. My parents are Jewish. I’m Jewish. I go to synagogue every single week now — I’ve been going the past few weeks.”

Conservative Stoneman Douglas students like Kashuv have said they felt marginalized by their peers and the news media after the shooting, which inspired young people across the country to try to register voters and get gun laws changed. Already, some political commentators on the right see Harvard’s decision to rescind his admission as motivated by complaints from Parkland graduates who oppose Kashuv’s politics.

Patrick Petty, 18, a friend and former Stoneman Douglas classmate of Kashuv’s, who shares his conservative views on gun control, said he never heard Kashuv use racist language or make offensive comments like the ones revealed in Ali’s video. He acknowledged friction in school among some students over their differing views of gun control, though he said some classmates quietly shared conservative opinions like theirs.

“If somebody really had an issue at the time, they would have taken it to a teacher or administrator,” said Petty, whose younger sister, Alaina, was killed in the shooting. “The fact that they didn’t just proves that it’s a political hit against Kyle because of his views.”

Harvard has faced other recent criticism for its handling of politically fraught matters. In May, the university did not renew the appointments of the first two African-American undergraduate faculty deans in the school’s history — both of them law professors — after protests from students who were unhappy that one of the deans took on the disgraced movie producer Harvey Weinstein as a legal client.

Kashuv did not explicitly accuse Harvard of making a politically motivated decision. He did say he had not spent time since the shooting with the students who had shared in the Google Doc chat that included the comments highlighted in the video, in part because of their disagreements over gun control.

“We’ve just drifted apart,” he said. “They don’t like my political views.”

He said he has other friends who do not share his politics, and that several of them reached out Monday to offer their support and tell him they thought Harvard had gone too far.

Other Stoneman Douglas graduates, however, appeared to welcome the news that he would not be going to one of the nation’s most prestigious universities. Some made vague comments on social media about “consequences”; some sent Kashuv “thoughts and prayers,” a gesture that victims of gun violence have seen as an empty one, especially coming from opponents of gun control.

This article originally appeared in The New York Times.