Meanwhile, North Korea is in purdah as it finalises its stance, and is refusing all contact with the US administration and even US-based groups working outside of official negotiation and mediation processes.

The first outcome of Pyongyang’s ongoing re-evaluation is the restructuring of the negotiating team. The powerful United Front Department has seemingly been sidelined in favour of the foreign affairs ministry.

The ministry, compared to the department, is a level removed from the decision-making process, so this is not necessarily a change for the better.

Meanwhile, the military has been also sidelined from the negotiations, and their continued support for the process is far from assured.

Equally, the rhetorical attacks by the rapidly rising Vice Foreign Minister Choe Son-hui on US Secretary of State Mike Pompeo and National Security Adviser John Bolton are unhelpful, and make it impossible for Trump to marginalise either man.

Pompeo and Bolton are on opposite sides of the battle inside the US administration on North Korean policy. There is no third position. Pompeo, while deeply sceptical of Kim’s commitment to denuclearise, is more pragmatic. Bolton, on the other hand, is ideologically opposed to appeasing Pyongyang and will continue to sabotage the process.

The crisis is the consequence of drought, floods and trade sanctions on spare parts for farm machinery, pesticides and fertiliser. There is a shortfall of 1.4 million tonnes of cereals and North Korea is delivering barely half of the minimum needed to millions already suffering from inadequate diets.

Any attempted relief is hindered by sanctions impeding money transfers, procurement and delivery.

The question is whether Moon is prepared to face down Washington.

The one ray of hope is the stepping back from Bolton’s all-encompassing definition of denuclearisation. Bolton’s definition swept up civil alongside military nuclear programmes, intermediate-range missiles with intercontinental ballistic missiles, included chemical and biological weapons and North Korea’s 3,000 nuclear scientists and engineers.

The working definition of denuclearisation now covers the production and storage of nuclear weapons-grade material and weapons – back where it all started.

What is on offer and what must be delivered is also clearer on the political and economic side. At the minimum, Trump wants a quick deal to mesh into his domestic road map to re-election, but is willing to contemplate a slow delivery as long as this is front-loaded.

They might even come to terms with inspected oversight of civil nuclear power and the launching of North Korea’s satellites. That timetable would mean a third summit this year. This last best chance would require serious preparatory work by both sides.

The elephant in the room remains: security guarantees for North Korea.

If the US were to end its hostile policy, what better demonstration of commitment than withdrawing US forces from the peninsula?

It is inconceivable that this will not be on the table at a future meeting even if ultimately Pyongyang would allow Washington to buy out the demand with concessions.

At the Kim-Trump summit in Hanoi, Washington proposed an infrastructure fund to which the US would not contribute, but whose contributors would include South Korea, which can contribute US$10 billion from its special contingency fund for reunification, and Japan, which can contribute a similar amount as delayed reparations for colonial depredation.

Whether Tokyo will agree and sign over the money is far from certain.

For Japan, the message from Hanoi was that any summit between Prime Minister Shinzo Abe and Kim would be predicated on Tokyo’s modifying its hostile position.

It would be no surprise – and suit Washington – if some time after the G20 summit in Osaka, there was a blitzkrieg summit in Pyongyang.

Glyn Ford is the author of “Talking to North Korea”