There was never a chance Donald Trump or Vladimir Putin were going to walk away from this summit declaring it a flop, a failure.

Neither man is built for that. And so it was, a historic low in relations between the two countries was now over.

"I hold both countries responsible" Mr Trump said.

"I think that the United States has been foolish. I think we've all been foolish.

"I think we should have held this dialogue a long time ago. A long time — frankly before I came to office.

"I think we're all to blame."

The two presidents had agreed to move on, co-operate, rebuild. And when Mr Trump was asked at the news conference who he believes when his intelligence agencies tell him it really was the Russians meddling in the US election, his answer was stunning.

"People came to me, [national intelligence director] Dan Coates came to me and some others, they said they think it's Russia," Mr Trump said.

"President Putin says it's not Russia. I don't see any reason why it should be."

So the President of the United States prefers the word of Vladimir Putin to the collective weight of the best resourced intelligence agencies on the planet. His people. The ones sworn to defend the United States.

Mr Putin was also asked about collusion. Show me a single fact, he challenged the reporter.

"This is nonsense," he said.

Sorry, this video has expired Vladimir Putin insists his country has no compromising material on Donald Trump (Photo: AP/Pablo Martinez Monsivais)

An 'incredible offer'

Then came what Mr Trump described as an "incredible offer".

The Russian President said his investigators would co-operate with the Mueller investigation into collusion, including on the recently indicted 12 Russian military intelligence officers .

"Send in an official request to us," he said. "Then we would interrogate these individuals who he believes are privy to some crimes. Our enforcement officers are able to do this."

He then went further. Robert Mueller's team could come in person to Russia and interview those accused of meddling in the 2016 election.

Donald Trump was excited.

"I have great confidence in my intelligence people," responded Donald Trump .

"But I will tell you that President Putin was extremely strong and powerful in his denial today. And what he did is an incredible offer.

"He offered to have the people working on the case come and work with their investigators with respect to the 12 people. I think that's an incredible offer."

Even some on Donald Trump's favourite news channel, Fox News, weren't buying this bromance with one host describing his performance as "disgusting" and "wrong".

Republican senator Jeff Flake, who is no friend of Trump's, went further on Twitter.

"I never thought I would see the day when our American President would stand with the Russian President and place blame on the United States for Russian aggression. This is shameful."

It is one thing to accuse the President of gullibility, stupidity or political opportunism, but questioning his fundamental loyalty to the United States is on another level.

Trump comes off unpatriotic in his meeting with the pragmatic Putin. ( Reuters: Kevin Lamarque )

If a view he has been unpatriotic was to take hold, then it could well be the beginning of the end for Donald Trump. Of course he would describe any such interpretation as "fake news".

He will defend his relationship with Vladimir Putin as good for everyone. Yes, the world. And if it means real progress towards cutting nuclear weapons stockpiles and deterring nuclear proliferation then he could fairly claim talking to "competitors" like Russia is a definite plus.

Putin's pragmatic view

Mr Putin takes a more pragmatic view of this newly energised relationship.

"Where do you get this idea that President Trump trusts me or I trust him?," he asks.

"He defends the interests of the United States of America and I do defend the interests of the Russian Federation."

Not friends, not enemies, but the US President represents a powerful nation that must be managed, massaged, influenced in a way that works for Russia.

And given the effusive praise coming from Donald Trump for his Russian counterpart it would appear that process is working swimmingly for the KGB agent-turned-President.

What summit?

There is no doubt Mr Trump is hoping his overseas interventions will pay off handsomely at home.

Certainly he made the most of vague promises at the Singapore summit from North Korea's Kim Jong-Un to get rid of his nukes.

And the President billed himself as the NATO enforcer, bringing errant nations to heel and making them pay their fair share.

He told UK Prime Minister Theresa May, via a newspaper interview, that her Brexit plans were doomed and her rival Boris Johnson would make a good prime minister. Then he slammed into reverse, saying she would succeed whatever Brexit deal she cut because she was a tough smart woman.

What are we to make of this summit? Are there major enforceable agreements? Not really.

Is there a reset in what has been a dangerously decaying relationship? That's a clear yes.

But issues like the invasion of Crimea, the war in Ukraine, the downing of MH17 and the Novichok attacks in the UK remain disputed and unresolved. None of which are likely to harm the President at home.

But the faintest whiff of disloyalty to his own country could really hurt.