WASHINGTON (NYTIMES) - Tuesday (Feb 11) was shaping up to be the kind of news day that makes President Donald Trump unhappy: One in which he saw himself losing control of the narrative in the face of wall-to-wall coverage of his Democratic rivals in the presidential primary in New Hampshire.

Mr Trump had other ideas.

In a provocative early-morning tweet in which he charged, "Wow, Bloomberg is a total racist!", the President of the United States delivered to his millions of Twitter followers leaked audio from 2015 in which Mr Michael Bloomberg, the Democratic presidential hopeful and former New York mayor, offered an unflinching defence of stop-and-frisk policing for which he has since apologised.

Originally posted by a liberal blogger on Monday night, the clip underscored one of Mr Bloomberg's key vulnerabilities in the Democratic primary as he seeks to convince voters that he is sorry for the aggressive policing tactics his administration used against minorities in New York.

In the clip, Mr Bloomberg can be heard saying that "the way you get the guns out of the kids' hands is to throw them up against the walls and frisk them".

For Mr Trump, it was an opportunity to try to shape the coverage of the Democratic contest more to his liking.

Like an assignment editor at a tabloid newspaper, the President poured accelerant on the story, aided by his oldest son, Mr Donald Trump Jr, and his campaign manager, who helped fuel a social media firestorm, already underway, that had the hashtag "#BloombergIsARacist".

Within an hour, Mr Trump had deleted his own tweet without explanation. But by the afternoon, the hashtag was trending on Twitter and cable news programmes, including on CNN and MSNBC, where guests were still talking about the audio clip - and Mr Trump's meddling.

Same tactics

Mr Trump has himself been a vocal supporter over the years of the same police tactics that Mr Bloomberg once championed, and the very accusation he was levelling against his potential rival - that he is a racist - conjures up one of the most often repeated accusations against the President himself.

Asked about that, Mr Jason Miller, a spokesman for Mr Trump's 2016 campaign who spent the morning talking about the Bloomberg audio clip on a Trump-backed podcast and radio show, shrugged.

"I think Trump is trying to draw out Michael Bloomberg," he said.

The tweet, Mr Miller added, "was hugely effective".

"If President Trump had not done that," he continued, "you wouldn't have seen all the cable news coverage. Now that's injected right into the middle of the conversation."

On Tuesday afternoon, Mr Trump kept it up in the Oval Office, where he accused Mr Bloomberg of pandering for votes when he apologised for the stop-and-frisk policy at a Brooklyn church in November.

Uncharacteristically, the President also suggested that he deleted his tweet about the audio clip because he was worried about being too divisive.

"I put something out and it was pretty nasty," Mr Trump told reporters. "And I thought, you know, I'm looking to bring the country together, not divide the country."

Hijacking the news cycle

The morning of presidential media distraction was a reminder, if anyone needed one, that the first reality show star turned president has mastered the art of hijacking the modern Internet-dominated news cycle, taking old but not well-known information and hyping it to make it feel new and potentially damaging for one of his political enemies.

Mr Trump has been warily eyeing Mr Bloomberg, who has already spent hundreds of millions of dollars in television ads attacking the President. The audio was posted hours after Mr Bloomberg polled in third place in a national survey of the Democratic primary conducted by Quinnipiac University. His support among black voters was higher than that of Senator Bernie Sanders, who is on his second presidential campaign.

In a statement shortly after the President's tweet, Mr Bloomberg admitted that stop-and-frisk was "overused" and again apologised for not eliminating the policy "faster and sooner".

But he lashed out at Mr Trump, saying the morning's post was the "latest example of his endless efforts to divide Americans".

"The President's attack on me clearly reflects his fear over the growing strength of my campaign," Mr Bloomberg said. "Make no mistake Mr President: I am not afraid of you and I will not let you bully me or anyone else in America."

Mr Bloomberg's record on stop-and-frisk has received limited attention since he began running for president in November. The three-term New York City mayor defended the aggressive policing tactic for years, even after a federal judge ruled that it had violated the constitutional rights of minority men in New York.

He apologised for it only after he announced his presidential campaign. In the weeks since, he has mischaracterised when and why he made changes to the policy in 2013, his final year in office.

Snippets of Mr Bloomberg's blunt comments about the stop-and-frisk policy during a speech at the Aspen Institute in 2015 had previously been reported. But the audio, edited to string the most damning statements together, was taken by Mr Trump and his online supporters and shared repeatedly on Twitter.

'It works'

But Mr Trump has his own history of support for stop-and-frisk.

In 2016, he endorsed the policy, saying it had been used effectively in New York City. And in 2018, after he was president, Mr Trump suggested that police departments in heavily minority cities, like Chicago, ought to use such aggressive tactics. The police in that city should "strongly consider stop-and-frisk", Mr Trump said in a speech at the time.

"It works, and it was meant for problems like Chicago," the President said. The White House declined to comment about Mr Trump's tweet or his history of support for the policy.

Mr Trump has also repeatedly been accused of racism, both as a 2016 presidential candidate and during his time in office. His efforts to curb the use of food stamps, his administration's attempts to dismantle provisions of the Affordable Care Act and his restrictive immigration policies have all been denounced as harmful to blacks and Latinos.

Mr Trump has often turned the criticism he gets back on his opponents.

When he was running against Mrs Hillary Clinton in 2016, Mrs Clinton said during their third debate that President Vladimir Putin of Russia preferred having "a puppet as president of the United States". Mr Trump replied, "No puppet - you're the puppet."

When The Washington Post reported the existence of the Access Hollywood tape that featured Mr Trump bragging about grabbing women's genitals, he responded by bringing women who had accused Mr Bill Clinton of sexual misconduct to the second presidential debate two days later.