WASHINGTON — When President Obama sent his inaugural Twitter post from the Oval Office on Monday, the White House heralded the event with fanfare, posting a photograph of him perched on his desk tapping out his message on an iPhone.
The @POTUS account — named for the in-house acronym derived from “President of the United States” — would “serve as a new way for President Obama to engage directly with the American people, with tweets coming exclusively from him,” a White House aide wrote that day.
But it took only a few minutes for Mr. Obama’s account to attract racist, hate-filled posts and replies. They addressed him with racial slurs and called him a monkey. One had an image of the president with his neck in a noose.
The posts reflected the racial hostility toward the nation’s first black president that has long been expressed in stark terms on the Internet, where conspiracy theories thrive and prejudices find ready outlets. But the racist Twitter posts are different because now that Mr. Obama has his own account, the slurs are addressed directly to him, for all to see.
Within minutes of Mr. Obama’s first, cheerful post — “Hello, Twitter! It’s Barack. Really!” it began — Twitter users lashed out in sometimes profanity-laced replies that included exhortations for the president to kill himself and worse.
One person posted a doctored image of Mr. Obama’s famous campaign poster, instead showing the president with his head in a noose, his eyes closed and his neck appearing broken as if he had been lynched. Instead of the word “HOPE” in capital letters as it appeared on the campaign poster, the doctored image had the words “ROPE.”
The accompanying message said “#arrestobama #treason we need ‘ROPE FOR CHANGE.’ ” It was addressed to @POTUS by a user calling himself @jeffgully49, who has posted other images of Mr. Obama in a noose, and whose Twitter profile picture shows Mr. Obama behind bars. “We still hang for treason, don’t we?” his post said.
The writer, Jeff Gullickson of Minneapolis, subsequently posted on Thursday that his reply to Mr. Obama had earned him a visit from the Secret Service at home. Reached for comment, Mr. Gullickson responded by asking in an email how much The New York Times would pay him for an interview.
White House officials and a Twitter spokesman said they could not determine the percentage of postings to Mr. Obama that were racist. But they appeared to be a small number in what was an otherwise social-media-fueled show of love for Mr. Obama, who was drawing followers at a breakneck pace — nearly 2.3 million by Thursday afternoon — and hundreds of worshipful messages that welcomed him to Twitter and praised him on everything from his appearance to his policies.
“I love you, @POTUS,” wrote one person, @camerondallas, who has nearly five million followers, in a posting marked as a favorite more than 15,000 times.
But there was one measure of a specific slur. According to analytics compiled by Topsy, a research company that collects and analyzes what is shared on Twitter, the number of postings that included Mr. Obama’s name and one particular racial epithet jumped substantially on Monday, the day of the president’s first posting, to 150.
One Twitter user who did not use that specific racial slur responded to the president with just two words: “Black monkey,” a comparison that was not uncommon. “Get back in your cage monkey,” another person wrote.
Josh Earnest, the White House press secretary, said that the language directed at Mr. Obama was unfortunately “all too common on the Internet,” and that officials would probably not spend much time trying to block abusive commenters from the president’s account.
“What we believe is that the president’s new Twitter handle is one that can be used to important effect and to communicate with the American people and to engage the American people,” Mr. Earnest said. “We’re pleased with the early response to it.”
The Twitter account @BarackObama, which was created eight years ago and is controlled by the liberal activist group Organizing for Action, has long been a target of racist postings, as has the official @WhiteHouse.
Top advisers to Mr. Obama, who pioneered the use of technology in his campaigns, regard such hate speech as a relatively minor price to pay for the opportunity Twitter and other platforms provide to reach voters directly. Twitter, which has been criticized for not cracking down on so-called trolls who post abusive or inappropriate comments on the social networking platform, does not police individual users or initiate its own action against them.
“The potential for anonymity allows people to say offensive, horrible things on Twitter that they would never say anywhere else, but we’re talking about a tiny fraction of the community,” said Dan Pfeiffer, Mr. Obama’s former senior adviser and longtime aide who pushed the president to engage on social media, including urging White House officials to create Twitter accounts.
“We know those sentiments exist, we know those comments are on Twitter or other social media platforms, but you’d be missing a terrific chance to engage with a lot of really good nontrolls if you stayed off of them because of the tiny fraction of people who are doing it.”
Still, the rise of social media, coinciding as it did with Mr. Obama’s political ascent, has made this president a frequent target of hate-filled Internet speech and threats. The phenomenon spiked during his campaign and the days leading to his inauguration in 2008 but has since subsided.
The Secret Service has a special “Internet Threat Desk” that monitors them, assessing whether they constitute a genuine danger and what should be done in response.
“People have the right to free speech,” said Brian Leary, a Secret Service spokesman. “We also have the right and an obligation to determine a person’s intent when they say something.”
The response can range from a conversation determining someone’s intent all the way up to working with the local United States attorney’s office to prosecute someone, Mr. Leary said.
Law enforcement agencies can also submit requests to Twitter when postings appear to pose immediate physical danger to someone, and Twitter will provide information about the account. A Twitter transparency report for the second half of 2014, the latest available, showed that the government had made more than 1,600 such requests. Twitter had furnished information in 80 percent of those cases.
“Like all of our technology industry peers, we do not proactively monitor content,” said Nu Wexler, a Twitter spokesman. “Individual users and law enforcement authorities — including the U.S. Secret Service — report content to us, and we review their reports against our rules, which prohibit violent threats and targeted abuse.”