Media playback is unsupported on your device Media caption Donald Trump: "I think the political press is among the most dishonest people that I've ever met"

Spoiler alert - before you read this you should understand that I am almost certainly disgusting, invariably dishonest and an inveterate liar. Well, that seems to be the considered view of Donald Trump on journalists.

At a news conference in Trump Tower, his hostility towards the fourth estate was off the scale. If you want a dictionary perfect definition of tetchy, watch this news conference.

The subject matter sounded so benign: it was about the money Trump is giving to veterans' charities following the fundraising event he held back in January when he'd refused to take part in one of the TV debates (for reasons that I can't even remember - something about there had been enough debates).

Anyway, spool forward to today and Trump had come to announce where the money would go. And reporters wanted to know why it had taken so long to make this announcement, where the money had gone and how it was being distributed.

It wasn't just that he didn't like the questions. There was a slightly menacing, intimidating air to the way he dealt with the inquiries.

Let me give you a flavour. On the press in general he had this to say: "I think the political press is among the most dishonest people that I've ever met. The media is made up of people - in many cases, not all cases - of bad people. The press should be ashamed of themselves."

One reporter then asked whether this would be the way journalists would be treated during the general election campaign and if he became president. "It is going to be like this," he said.

Media playback is unsupported on your device Media caption Jon Sopel explains why Donald Trump wants the biker vote

And some people he picked off individually: "This sleazy guy right over here from ABC. He's a sleaze in my book," Trump said pointing to ABC reporter Tom Llamas. "You're a sleaze because you know the facts and you know the facts well."

Then to the CNN reporter Jim Acosta, whom I have met many times at Trump events, he said sarcastically "you're a real beauty".

Having covered Donald Trump for the best part of a year, I thought I had lost the capacity to be surprised. But this excoriating attack on journalists - particularly political journalists - was quite something.

There are two aspects of this that interest me. The first is the irony.

The remarkable thing that has struck me as a British correspondent living in Washington, and who is used to a robust relationship between journalist and politician, is how Trump has been treated with kid gloves.

Given how many interviews Trump has given (and you need to count them in the hundreds, possibly thousands), very few have stood out as asking the key questions - and then following through when you get an evasive answer.

If you want a "for example", how about the Trump pledge to ban all Muslims from entering the United States. Was he ever pressed on how this would be implemented given how few countries ask for your religion to be listed in your passport? Was he pressed about the constitutionality of such a move?

These are serious, respectful, challenging questions that any candidate has to be asked if they seek to govern.

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There has also been a tendency among the cable channels to give a massively disproportionate attention to every live event that Trump does.

It's understandable: his rallies are more exciting, more unpredictable and more likely to yield a story - but what about the need to give balance to other candidates?

Is it overly cynical to suggest that Trump drives ratings, ratings drive ad revenues and TV companies have to make profits? So let's not worry too much about the editorial/ethical questions - let's go with the Trump event.

It should also be said that Mr Trump knows this - and will give you extensive details about how his presence on TV drives up the audience

Or take his tax returns, which he is still refusing to reveal because, he says, they are still being audited by the IRS. He insists once that process is complete he will release them.

Now a number of experts have said there is nothing stopping him from publishing them - in line with all presidential candidates going back decades. But so far, the pressure from the press has not reached the critical mass so that he feels obliged to reveal his financial affairs.

In the UK, the press in full cry can be an irresistible force. I have not seen that here.

Image copyright Getty Images Image caption Trump has attacked media throughout his presidential campaign.

The interesting thing is the extent to which Mr Trump really bristles at being questioned. I suspect when you are a billionaire property mogul you are used to deference. When you are a politician you need to get used to scrutiny.

There are two possible explanations - one is that he has an incredibly thin skin and just doesn't like having his motives questioned. The other is that there is deliberate strategy - if you intimidate, and threaten not to give interviews to networks that irk you then maybe they will buckle and give you an easy time.

I know many American journalists whose unease is not driven by how toughly they are treating the presumptive nominee, but by how softly.

Perhaps his combativeness toward media is part of his strategy to appeal to his supporters, whose disdain for journalists is as great as their distaste for the political elite.

Maybe Mr Trump has realised the harder he rails against the news media, the more respect he earns from a brand of voters who could elect to him to office.

There has always been an uneasy relationship between press and politicians. And rightly so. We have different objectives.

There's the famous HL Mencken quote from decades ago when he said that the relationship between a journalist and a politician ought to be the same as a dog and a lamp post - and I have always hated it.

The presumption is that we are pure, and all politicians are venal and deserve the crap kicked out of them. Nearly all the politicians whom I have come to know have been motivated by a commitment to making the world a better place - yes, they may be ambitious, self-important people - but tell me one walk of life where you don't find people like that.

It is our job to test our elected officials, to subject them to scrutiny, to ask the questions the public want answering and hopefully to be fearless in our pursuit of those questions. And to do so respectfully.

That is our job, and a free press able to do that is one of the cornerstones of a liberal democracy.

To rework the Mencken quote, Mr Trump seems to think that we are the lamp post.