The 45th president and his predecessor had seemed to have put past controversies behind them. Now a series of early-morning tweets about a ‘new Watergate’ have reawakened their enmity

Saturday’s extraordinary attack by President Trump on his predecessor should come as little surprise in at least one respect. It proves, for anyone in any doubt, the depth of hatred between the two men: a discord that has bubbled to the surface in various bizarre ways over the past decade.

Obama endured years of Trump-led “birtherism” conspiracy theories – claims that Obama’s published birth certificate was a forgery, and that his actual birthplace was not Hawaii but Kenya. This often formed the basis of thinly veiled attacks on Obama’s African heritage, at a time when Trump had no platform other than being a reality TV star.

In early 2011, Trump told the Conservative Political Action Conference (CPAC): “Our current president came out of nowhere. Came out of nowhere. In fact, I’ll go a step further. The people that went to school with him never saw him; they don’t know who he is. Crazy.”

Trump's evidence-free wiretap claim follows rightwing Obama 'coup' stories Read more

Then came the now-notorious 2011 White House Correspondents’ Dinner, in which Obama joined comedian Seth Meyers in publicly humiliating the thin-skinned future president. Obama joked that he was glad Trump had rejected the birther conspiracy so that he could get back to real issues that matter, such as “did we fake the moon landing?”, “what really happened in Roswell?”, and “where are Biggie and Tupac?”.

Through the 2016 campaign, the pair appeared to establish a certain cordiality. Trump praised the president at rallies – an effort, perhaps, to draw attention to both men’s differences with Trump’s opponent, Hillary Clinton. With 53 days to go to the election, Trump called a news conference to announce he was finally rejecting birtherism – although he took the opportunity to claim Clinton had started it in the first place. But with only days to go and the polls tightening, the gloves came off.

Obama told a rally in Florida that Trump’s aides were trying to curb his Twitter habits. “In the last two days, they had so little confidence in his self control, that they said: ‘We’re just going to take away your Twitter,’” Obama said to a laughing crowd. “If someone tweets at three in the morning because Saturday Night Live made fun of you, you cannot handle the nuclear codes.”

After the election, Obama and Trump were cordial, if only publicly, and perhaps in Obama’s case only in a bid to preserve his legacy on climate change, healthcare and foreign policy.

The former president congratulated Trump on his victory, saying his White House team would “work as hard as they can to make sure this is a successful transition for the president-elect.” Trump visited the White House and stayed far longer than is customary. But by late December, the relationship had broken down again.

Obama told former aide David Axelrod that he could have beaten Trump. “If I had run again and articulated it, I think I could’ve mobilised a majority of the American people to rally behind it,” he said. Trump shot back: “Obama said that he thinks he would have won against me. He should say that but I say NO WAY! - jobs leaving, Isis, OCare, etc.”

Facebook Twitter Pinterest The president has accused his predecessor of wiretapping Trump Tower before the election. Photograph: Mark Lennihan/AP

During a trip to Pearl Harbor alongside Japanese prime minister Shinzo Abe, Obama warned against “the tug of tribalism” and “the urge to demonise those who are different”.

Having repeatedly praised Obama’s efforts to ensure a smooth transition, Trump reversed course on this subject also. “Doing my best to disregard the many inflammatory President O statements and roadblocks,” he wrote. “Thought it was going to be a smooth transition – NOT!”

Then the course of the relationship took another twist, with Trump saying he was “getting along very well” with the outgoing president “other than a couple of statements that I responded to”. Trump added: “We talked about it and smiled about it and nobody is ever going to know because we are never going to be going against each other.”

The back-and-forth didn’t cease entirely. Trump condemned the Obama administration’s “horrible Iran deal” and indicated he would support an aggressive new wave of Israeli settlement-building in the occupied territories. Obama refused to block a move censuring Israel in the UN security council.

Still, at least in Trump’s estimation, the bromance appeared to be back on. Trump told Fox News host Bill O’Reilly he had the feeling his predecessor had a positive opinion of him, saying, “I don’t know if he’ll admit this, but he likes me.”

But now with Saturday’s social media outburst, the relationship appears once again to be on the rocks. It started with the early-morning Twitter attack on Obama for “McCarthyism”, having allegedly ordering a pre-election wiretap. “Terrible! Just found out that Obama had my ‘wires tapped’ in Trump Tower just before the victory. Nothing found. This is McCarthyism!” he wrote, calling the ex-president a “bad (or sick) guy”.

Like so many of Trump’s pronouncements, the assault appears to have been inspired by an item from a favourable news source. On Thursday, Breitbart News, the conservative site with close ties to current White House chief strategist Steve Bannon, published an article based an a report by a rightwing radio host Mark Levin claiming that Obama’s “police state” actions – and not the Trump campaign’s contacts with Russia – should be the subject of investigations.

Levin, citing reports in November by former MP Louise Mensch and the Guardian’s Julian Borger, drew attention to a June 2016 request by the Obama administration, lodged with the US Foreign Intelligence Surveillance Court, to monitor communications involving Trump’s staff.

The request, which is believed to have named Trump, was denied. But a second request was granted in October, allegedly on the grounds that a computer server possibly connected to the Trump campaign contained links to two banks; SVB Bank and Russia’s Alfa Bank.

By January, the right-leaning National Review was drawing the threads together, suggesting it was no longer far-fetched that the surveillance court could be used against political enemies.

In the duel of news narratives, the Breitbart story offers Trump an element of diversion from a week that began with a well-received speech to Congress but ended with a now familiar narrative of Russia-related accusations, leaks and self-administered mishaps.

The Breitbart/Levin story offers Trump a counter to an impressive list of difficult stories: the salacious dossier compiled by a former British spy; the expulsion of Russian diplomats over alleged election interference; three investigations into the Trump campaign for suspected Russian ties; the resignation of national security adviser Michael Flynn; and, last week, problems stemming from the failure of attorney general Jeff Sessions to mention two meetings with the Russian ambassador at Senate confirmation hearings.

The battle between the two men continues. The form it takes may have changed: the enmity continues.