PARIS — America is run by a carpet seller. Donald Trump negotiates on the international stage the way he did with building contractors and local communities back when he was a developer: fiercely, stingily, and with only his interests in mind. His goal then was to increase his financial capital. Now, he looks to consolidate political capital — by snatching concessions from other countries, those where he has no voters.

It is a radical novelty, but at the same time the continuation of a shift that began half-a-century ago, and the perpetuation of an old American tradition. A radical novelty because never has a leader of a great power acted in such fashion. The continuation of an already old movement because this policy characterizes a nation whose domination has been declining since the 1960s. And a tradition because isolationism has punctuated the history of the United States since George Washington and Alexander Hamilton.

Either way, America is turning its back on the world. It is time for the world to act accordingly, before the seeds of discord planted by the president of the United States germinate and grow.

Actually, that is already the case. In the international institutions where the president withdrew the American pillar to cause their collapse and thus prove to his electorate that he is a man of his word and a man of action, the leaders of the other countries have (for the time being) managed to safeguard the building, sometimes leading Trump to revise his position. And other world institutions are springing up, far from the United States.

It is time for the world to act accordingly, before the seeds of discord germinate and grow.

Let's begin with the first decision made by the new White House occupant. The day after his inauguration, he withdrew his country from the Trans-Pacific Partnership (TPP), which was intended to bring together countries from the Americas and Asia, not including China. But that withdrawal didn't kill the TPP. The other countries continued to negotiate as if nothing had happened. So much so, in fact, that later, Trump let it be known — first in January in Davos, then in April — that the United States could end up rejoining the agreement, even though it was designed by his abhorred predecessor, Barack Obama, and his despised rival, Hillary Clinton.

International bodies and geopolitics

Trump's offensive against the mechanics of trade goes well beyond the TPP. The American president dreams of breaking up the World Trade Organization (WTO) and replacing it with bilateral power struggles. He's now decided to block the appointment of new judges to the WTO court that settles disputes between countries. "We will need to get used to a multi-speed WTO," says Pascal Lamy, who was its director-general for almost a decade.

The idea seems far-fetched given how the United States has played a driving role in the history of the organization. But WTO member countries are quietly considering ways to get around the U.S. obstructionism. The example could come, for once, from UNESCO. When Ronald Reagan was president of the United States, he withdrew the country from this UN agency that wants to bring people together through education and culture. UNESCO survived. So much so that the United States rejoined the institution in 2003, before announcing a new withdrawal at the end of 2017.

We will need to get used to a multi-speed WTO.

The other international institutions forged in Bretton Woods in 1944 under American tutelage could also suffer the Trumpian wrath — starting with the International Monetary Fund (IMF). But many countries have learned the lessons from the 1997-1998 Asian crisis and from the eurozone crisis of 2011-2012. They are trying to limit their current account deficits, the crisis management of which is the IMF's real raison d'être. And Europe has formed the embryo of a European Monetary Fund with the European Stability Mechanism, although much remains to be done.There's also the World Bank, which aims to finance the development of poor countries. In this case, it was China that offered an alternative with the launch, in 2014, of its Asian Infrastructure Investment Bank (AIIB). Fifty-seven countries have joined the initiative, a third of them Europeans. And unlike the United States with the World Bank, China does not have a right of veto.

Donald Trump has also taken Washington out of another international field: the fight against global warming. This did not prevent the other countries from trying to implement the Paris Agreement. There is also disagreement within the United States. Cities like New York, big companies like Google and Facebook, and states like California have ignored the presidential decision by saying loud and clear that they will pursue their efforts.

Still, it is difficult to imagine a new international order without the United States. Washington remains active on the world geopolitical stage, both in the UN Security Council and on the ground (as the recent airstrikes in Syria have shown). After the withdrawal of the United States from the Iranian nuclear agreement, the five other signatory countries (China, Russia, France, the United Kingdom and Germany) have indeed decided to continue. But the measures Trump decided against Iran will hit companies doing business in these countries, particularly European companies.

Like it or not, the situation we now face is this: To exist without America, the world will have to act against America. The storm is approaching.

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