Donald Trump perhaps got the clearest idea of what he might face if he becomes US president during a news conference in New York.

He called everyone together to give details of the money he'd raised for veterans' charities.

Tuesday's event was pulled together after the Washington Post started asking who got what and when from the $6m Trump told everyone he'd raised.

Remember back in January, before the Iowa caucus, the man who is now the Republican Party's presumptive presidential nominee fell out with Fox News.

He thought they were being "unfair" to him. And so rather than attend the scheduled debate they were to host, he held an alternative event across town.

And he was going to raise money for ex-servicemen and women.

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During that gathering, which was broadcast live on all cable news channels that weren't Fox, he told the crowd he would give $1m of his own money.

And at one point, from the podium, he announced they had raised more than $6m.

On his website, there was a page where the public could go to donate.

Given the fuss he made at the time, and given that he asked the public to chip in, it was only right that people found out what he'd done with the money.

Last week, the Washington Post discovered that the businessman had not yet made his own donation.

So the media was called to Trump Tower in Manhattan to face an angry and defensive Trump.

He said that there was a need to check every organisation that was going to get the money - even though the group that got the largest donation was well known to him.

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He attacked everyone for not giving him credit for raising the money and for checking up on him to see if he distributed the money.

He insisted he wasn't looking for publicity: "The press should be ashamed of themselves."

He then went on to brand one reporter "a sleaze" and sarcastically refer to another as "a beauty".

Trump then set off on an attack which was quite remarkable, even for a man who has spent most of his campaign branding the media as "dishonest", "lowlifes" and "horrible people, the worst".

When asked whether the American public could expect a similar dynamic if he won the White House, he replied: "It's going to be like this. I'm not changing."

The exchange, which lasted about 40 minutes, offers up a few interesting points.

First of all, this seemed to signal some sort of change. The media were more combative and it was clear that this unsettled Trump. He was angry that they were digging into his statements and boasts.

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Uncomfortable questions were handled as if they were criticisms, the candidate's infamous thin skin shining through.

Then there was the statement that Trump won't change. People have been asking for a "more presidential" Trump.

And there have been snippets, mere moments, the odd speech, where that side of his character emerges.

It's clear he believes he owes his success to the way he's conducted his campaign so far, and there's no need to change. The professional political operatives and the pollsters will tell him he needs to broaden his appeal in the general election.

However, in the Trump office in New York, there is a sign which says "Let Trump be Trump".

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It may be that Trump cuts back on his news conferences. He didn't come out of this well.

But no Republican candidate ever suffered from attacking the media and so the damage may be almost imperceptible.

And despite it all, Trump still makes himself available to the media.

He's held several news conferences in the past few weeks.

The closest we've had from Democratic Party rival Hillary Clinton was a few hurried questions to the candidate in a diner in Minnesota. That was on March 1.