Trump's awkward relationship with Barack Obama
Election campaigns can be vitriolic, but the relationship between president and successor is usually more civil afterwards.
Monday 6 March 2017 06:04, UK
Donald Trump's public attack on a former president is extremely unusual.
While election campaigns are laced with vitriol once the victor enters office there's at least a public respect for the former White House occupant.
But in an unprecedented attack, President Trump has called the former president Barack Obama "sick", saying he should be prosecuted for illegally wiretapping him.
Donald Trump and Barack Obama have history.
Mr Trump began his attack in 2011 when he started to .
That same year, after releasing his birth certificate, Mr Obama .
The room erupted around an expressionless Mr Trump as Mr Obama cracked jokes about his birther claims, painting him as a ridiculous conspiracy theorist.
His humiliation was public and stinging but Mr Trump didn't change his course - he continued questioning Mr Obama's birth and legitimacy for several years.
During the 2016 campaign both men took regular swipes at each other.
Mr Obama mocked Mr Trump again - this time over his use of Twitter, saying: "If somebody starts tweeting at three in the morning because SNL made fun of you, then you can't handle the nuclear codes".
Candidate Trump went a few steps further, suggesting Mr Obama had some sort of sympathy or even connection with Islamic terrorists.
"There's something going on," he said in June last year.
He then claimed that Mr Obama founded IS.
But the sour tone sweetened with victory.
After winning the 2016 election the .
Mr Trump called his predecessor a "good man" with whom he had "great chemistry".
A month ago, in an interview with Fox News, Mr Trump said of Mr Obama: "We get along, I don't know if he'll admit this, but he likes me. I like him."
Then something changed.
Mr Trump began accusing Mr Obama of being behind leaks and just around the time that right wing media outlets like Breitbart started reporting that an Obama "shadow government" was plotting to derail Mr Trump's presidency.
Breitbart's story about Obama wire taps started circulating and Mr Trump appears to have seized it and cited it as fact.
Mr Trump has defined a new enemy at whom he can direct all the ire he feels about the .
Without evidence, it's hard to see how this goes any further.
Twice now, Trump officials have been caught misleading or lying about their contact with the Russian ambassador.
Questions over his campaign's links with Russia will continue - and that is perhaps the true source of the president's anger.