Interview by Julia Baird, digital producer Amy Sherden.
The moderator who drew the wrath of Donald Trump for the way he conducted a Republican presidential debate last year has defended the conduct of Fox News host Megyn Kelly following her encounter with the vocal political candidate.
Mr Trump withdrew from the televised encounter, scheduled for Thursday night (local time) in Des Moines, Iowa, in irritation at host Fox News for allowing Kelly to moderate after her questioning angered him in a debate last year.
CNBC’s chief political correspondent John Harwood felt the ire of Trump last October when he asked the candidate, “Is this a comic-book version of a presidential campaign?”
He says now that while he could have framed his question differently, he does not apologise for making Trump uncomfortable.
Harwood has told the ABC's 7.30 that he sent a note to Kelly following Trump's withdrawal.
"I sent her a note today when this controversy arose and just said that she should know that her colleagues in the business understand, that this is not about her conduct or about anything she's done inappropriately," he said.
"It's about a political candidate trying to use whatever devices he can to advance his campaign [and he] has decided to settle on her and that's why it's happening."
Mr Trump's move means the last televised debate before Monday's Iowa caucuses — which kick off the state-by-state nominating race to choose candidates for the presidential election — will not feature the man who has dominated the Republican race for months and leads many opinion polls.
Harwood explains why Trump is so popular:
1. Trump has proven he's a tough guy
I wouldn't say the media is losing control but I would say that Donald Trump is taking control of the Republican nomination race.
Everything he's done - insulting his own party, insulting his colleagues, insulting the media - has given his supporters the impression that he's a tough guy who's not bound by the polite conventions that they're used to seeing and associate with an ineffective government.
2. Removing himself from the debate avoids potential problems
Polls out today show him ahead by 7 points over Ted Cruz, he's way ahead in New Hampshire, in South Carolina and if he can roll these victories together at the beginning, he has really got momentum for the Republican nomination - so he is removing a risky confrontation.
He also follows through on something that he's threatened to do multiple times ... where he's said 'I won't show up'. If you say that enough times and don't do it, people may wonder if you can be taken seriously.
3. He will steal the attention from other Republican candidates
By scheduling an event with veterans in Des Moines, at precisely the same time as the debate, that is going to be covered by other networks, he is really hurting the Fox debate and taking viewers away from it so not only is he avoiding a potential problem by being attacked ... he is also going to be dominating the headlines themselves by having this alternative event. It is quite a feat that I have really never seen in 30 years of following presidential politics
4. He shuts down rival sources of power
Megyn Kelly is the biggest star at Fox but she is certainly not someone who has been in Donald Trump's camp and so I think she is a rival power source within the conservative community because Fox is a conservative network and she has become his foil after the questions about his attitudes towards women that she asked in the first debate. He is playing this card and using it to some effect but it is not about Megyn Kelly, that's for sure.
5. He's defying sceptics
I did not think he was going to be in anywhere near this robust position. But if you look objectively, look at what we know about the standing of the race right now, you would have to say that Donald Trump is more likely than anyone else to win the Republican nomination.