The peace talks between North and South Korea wouldn't be happening without Trump's aggressive tweets

Donald Trump’s campaign for the US presidency was deficient in a host of ways, but most conspicuously in foreign policy. The only constants were his dubiously resonant slogan “America First” and his hope for better relations with Russia. Now, only “America First” remains. His ambition for a Russia rapprochement came back to bite him even before his inauguration.

The unlikely prospect of Trump as a foreign policy president, however, should not be dismissed so soon. Even as all of Washington still tut-tuts over the presidential tweets, and Robert Mueller’s Russia investigation circles ever closer, Trump has opened up the diplomatic terrain in a way that few recent presidents have done. The downside is mixed messages and a lack of direction; the upside – some unheralded opportunities.

The current week exemplifies both. It started with a visit from the Japanese prime minister, Shinzo Abe, who was one of the first foreign leaders to pay court to Trump after his election and has established what appears to be a warm dining and golfing relationship. It continued with the state visit of Emmanuel Macron – the first state visit to be hosted by the Trump White House. And it concludes tomorrow, as Washington has its sights trained on the first talks between North and South Korean leaders for a decade, which will be the vital prelude to – and how strange these words seem – a US-North Korea summit.

Not one of these developments could have been envisaged as happening in the way they have before Trump’s election. They are a product of this president’s highly personalised, spontaneous and seemingly erratic approach to foreign relations. But they are a reflection, too, of his unusual openness and flexibility – to which a few, a very few, have dared to respond.

One of them is Emmanuel Macron. The French president’s first meeting with Trump last year opened with a handshake that turned into an arm wrestle. Back in Paris, in a consummate judgement call, he invited the Trumps to Bastille Day. His reward was this week’s state visit. But it was no run-of-the-mill state visit, and there was no kowtowing. Macron set out for Washington saying that he would try to change Trump’s mind about leaving the Iran nuclear agreement. He left Washington conceding that he might have failed.

In between, however, Macron presented himself several times over – but most notably in his address to a joint session of Congress – as a proud president of France, a convinced exponent of European values, and someone who could, and was determined to, argue his case. He made several nods – of course, how could he not? – towards American staples: life, liberty, the pursuit of happiness and all that (which is actually easier for a French president to do than a UK prime minister, as after their respective revolutions they were essentially on the same side).

And it is also true that, nostalgic as ever for Camelot, Americans tend to take a shine to presentable young leaders.

All that said, though, Macron accomplished a state visit to the United States, hosted by America First Trump, without demeaning himself and without diluting the many US-EU disagreements. Was it only 15 years since French wine was being poured down drains in Boston, Freedom fries replaced French fries in congressional canteens, and the French were dubbed “cheese-eating surrender monkeys” – all because then President Jacques Chirac opposed US-UK plans for regime change in Iraq?

But it is not just, I think, that Macron’s improbable ascent to the French presidency, or his own self-confidence, allowed him to speak truth to the US president. It was also the less constrained – all right, less orderly – atmosphere around this White House, and the concerns felt in much of Europe about this president, that may have spurred him on. Indeed, is it not worth asking whether open and honest disagreement, even in the upper reaches of diplomacy, is really such a bad thing?

Something similar might apply to the talks to be held between the North Korean leader, Kim Jong-un, and the president of South Korea, Moon Jae-in. Last month Kim made a clandestine visit to Beijing, his first known sortie out of North Korea since becoming leader. Now, Kim will officially step into the South for the first time and conduct the talks in the full glare of publicity.

Until shortly before the Pyeongchang Winter Olympics, however, such a turn of events would have been unimaginable. Kim Jong-un was authorising nuclear missile tests that potentially threatened not just his neighbours but the United States. He and Trump were hurling very public insults at each other over the new and old media. The atmosphere was tense and there was talk of war. Whether Kim blinked first or whether – in eliciting a direct, albeit bombastic, response from Trump – Kim glimpsed a recognition of his own and his country’s dignity may never be known.

What is known, because the exchanges were there for all to see and hear, is that Trump was able to override diplomatic conventions in a way that several of his predecessors declined to do. And, yes, it was risky. But so, it must be said, is any other escalation towards war. In this event, word power averted weapon power. Trump’s gamble – so far – has paid off. After the initial US concession – the offer to meet Kim – the concessions from Kim came thick and fast. The nuclear programme would be on the table; tests would be suspended.

It is too early to judge whether the new North-South diplomacy can be sustained. But the promise of a summit with Trump, and the international validation this would provide, should be inducement enough for Kim to press on. The next objective should also be clear: not reunification – not yet, and perhaps not ever – but a formal peace treaty, with safeguards, that formally ends the Korean War. This could bestow the status and security that the North has craved. It could transform the Korean Peninsula and the region.

A more equal and honest relationship with Europe, as pioneered by a fearless French president, and a diplomatic breakthrough in Northeast Asia were hardly on the cards at the ill-starred beginning of the Trump presidency. And it could all end in tears. Risk, brinkmanship and open disagreement are not conventional tools of diplomacy. But may there not also be too much caution and too much searching for spurious common ground, when a dose of mutual respect and some direct talks might just do the trick?

We shall see. But if Donald Trump can bring Kim Jong-un in from the cold and defuse tensions around the Korean Peninsula, who would begrudge him the chance of trying to tame Vladimir Putin’s Russia? East-West relations are returning to the deep freeze. Conventional diplomacy has failed. Maybe Trump’s brand of risky realism offers a way of cutting through the wreckage.