From trade wars with allies to taming Kim Jong-un, Trump is convinced that bullying and aggression always pays

People have sucked up to him all his life and so they must still now. Yet, we are no longer talking ratings or rentals. This is about keeping the whole world safe and prosperous

President Donald Trump walks with Kim Yong-chol, former North Korean military intelligence chief and one of Kim Jong-un’s closest aides

For Donald Trump, aggression is always the best strategy. Even before becoming president, he deployed it as a property developer, as a reality television host and then a political candidate. Fear of causing offence never occurs to him. He pummelled his competitors in the Big Apple, left contestants on The Apprentice distraught and shredded “low energy Jeb Bush” and “little Marco”. He didn’t shy even from a fight with the Pope. In fact, he called him “disgraceful”.

His go-to stance now shouldn’t really surprise anybody. Who needs friends when you have billions of dollars and the biggest nuclear arsenal in the world? People have sucked up to him all his life and so they must still now. Yet, we are no longer talking ratings or rentals. This is about keeping the whole world safe and prosperous. And the question arises: when does he go too far and fall to the bottom of the abyss, possibly taking the rest of us with him?

Interestingly, people do seem surprised. Angela Merkel and Emmanuel Macron have clearly been taken aback by Trump deciding to ignore their pleadings and press the send button on new punitive tariffs on imports of steel and aluminium. Macron still hasn’t recovered from Trump picking dandruff off his lapel in the White House. To your corner!

He applied the metal tariffs to Canada and Mexico too. An infuriated Justin Trudeau evoked Canadians who’d died alongside Americans in war. That’s how hurt he is apparently feeling.

The condemnation of Trump was pretty universal. Special relationship Britain gets no pass either. “This is stupid – it’s counterproductive,” argued Francis Maude, a former trade minister. “Any government that embarks on a protectionist path inflicts the most damage on itself.”

So what does Trump do? He finds the wound and pokes it. Canada, he said in a tweet on Friday, has been treating US farmers “very poorly for a long period of time”. He also repeated his claim that Canada runs a trade surplus with the US. Never mind that it’s false. The US has outrun Canada in terms of the value of goods traded for each of the last three years.

Another drama in Washington on Friday was the visit by North Korea’s Kim Yong-chol to hand Trump a letter from his boss, Kim Jong-un, essentially begging that the proposed summit between them that Trump had agreed to and then rudely nixed be reinstated. It was the highest level North Korean delegation to the White House in almost 20 years. The letter-passing pantomime was watched by all the world. And Trump had the final word: yes. Summit restored.

So Trump is preening again. That the summit will happen – assuming it does now – is good for the world. Less good is the fact that this will lead Trump to believe in his way of going about business even more than he does already. He got to this spot by calling Kim “little rocket man” and then threatening war as if he really meant it. Perhaps he did. It could have gone nuclear.

His thinking on trade is similar. You could show him the official figures on US-Canada trade flows, but you will never convince him that the US hasn’t been swindled by its northern neighbour. And by Mexico and by the Europeans. He told his supporters in 2016 he would set all that straight and he is certain that getting rough is the only way to do it. Eventually, everyone else will buckle and deliver trade concessions to avoid greater injury in a protracted trade war.

You get the idea. Iran? Same. He told supporters he would quit the nuclear deal and he did, ignoring all of America’s usual allies again. No European namby-pamby him; he will force Iran to accept a tougher agreement or he’ll draw the regime into a trap that finally will be its undoing.

But does he think this path is without risks? The least of them may be diplomatic isolation. “This is really the US going it alone,” said Philip Levy, senior fellow at the Chicago Council on Global Affairs and former trade adviser in the George W Bush administration. “By assaulting all our allies, we leave ourselves standing unprotected and by ourselves in a way we really never have been.”

But the endlessly combative Trump could also bring combat to all the rest of us, economic and military, if things don’t go the way he imagines. The dialogue with North Korea could still end in acrimony and pitch the world back to the nuclear edge. A global trade conflict could break out, triggering worldwide recession. Shake your nearest foreign policy tree and any number of experts will fall out yelling how terrible an idea it is to add uncertainty to stress to danger in the Middle East by giving an excuse to Iran to go rogue. Or even more rogue.

And on trade, it appears Trump is just getting into his stride. The odds that the US, Canada and Mexico can now resolve their disagreements on renewing the Nafta free trade agreement just got longer. Now Trump is thinking too about blanket tariffs on cars and a total ban on German luxury cars. Because, you know, Cadillacs are so elegant. And Porches are so clunky.

No one would wish failure for the Kim-Trump summit. But if success helps convince Trump that bullying is the new best alternative to regular diplomacy, there will be other kinds of trouble for all of us eventually. Even for the Americans that voted for him.