CNN  — 

The biggest question clouding this weekend’s G7 summit in France is whether the President of the United States will blow it up.

It is a measure of the gulf between America and its allies and of how President Donald Trump has imposed his disruptive character on the world that everyone in Biarritz is bracing for a presidential eruption.

Given the President’s brazen, erratic behavior and mood in the last few days, the idea that he could repeat his tantrum and early departure at the last G7 summit in Canada last year cannot be ruled out. After all, he just pulled out of a state visit to Denmark because it refused to discuss selling Greenland.

Trump frequently flings vitriol across the Atlantic, criticizing foreign leaders who have spent the past two-and-a-half years trying, usually unsuccessfully, to work out how to handle him. His behavior is a promise kept to voters who believe that America’s friends have long taken advantage of its power and security guarantees.

Last month, for instance, he blasted French President Emmanuel Macron’s “foolishness” over a digital services tax that hit US companies and vowed to impose tariffs on French wine.

Anticipating trouble from Trump, Macron has abandoned the summit’s regular communique in an effort to take the focus off the disagreements set to rumble in the French surfing resort.

The G7, a group of rich democracies that comprise Britain, France, Germany, the US, Italy, Japan and Canada, is exactly the kind of globalized gathering that Trump and his supporters abhor and is in itself almost a rebuke to his America First philosophy.

The President prefers bilateral meetings where he can leverage superior US power, and he believes national sovereignty, not multilateral cooperation, is the foundation of international relations.

Furthermore, Trump’s sharp changes to US foreign policy have opened wide gaps with Europe on climate change, Iran, trade and Britain’s exit from the European Union that preoccupy other leaders.

“What we’re seeing, I think, is the institutionalization of America alone – I think this week we will see President Macron in France attempting to lead the six in a cogent way,” said Heather Conley of the Center for Strategic and International Studies during a conference call previewing the summit.

“The other countries are trying to figure out who takes up the new mantle, and can they hold on either until the US returns to that leadership role, if it will, or are they going to have to survive in these six dynamics without the US.”

The spectacle of Trump feuding with foreign leaders – captured at the G7 in Quebec last year in an iconic photograph – horrifies his critics and the US foreign policy establishment.

Which is exactly why Trump may see a political benefit in being the disgruntled odd man out at a meeting that some foreign policy analysts have started calling the G7 minus one.

Trump to tout strength of US economy

Still, there are also several reasons why Trump may find this summit more enjoyable and useful than most of his foreign trips.

To start with, he will get a chance to boast, since the winds of economic decline are beginning to sweep through Europe, which is in far worse shape than the US economy, despite recession fears.

“You will really hear the President hit home the message of the pro-jobs, pro-growth economic agenda, and what he’s done by way of the historic tax reforms, deregulation, investment policies, a focus on energy and free, fair and reciprocal trade,” a senior Trump administration official said on Thursday.

“We’ve seen growth rates that we didn’t think were possible just a few years ago. And you can contrast this to what’s happening in Europe, where growth is effectively flat.”

Trump has a strong political interest in helping to shake Europe out of its economic malaise, given fears that a follow-on effect could tip the US economy – his potential passport to a second term – into its first downturn since the Great Recession.

The problem is that many European leaders see Trump, his trade war with China and wielding of tariffs as a contributing factor to their problems, so agreement on next steps could be elusive.

Trump is also threatening to divide the group over his calls for the readmission of Russia, which was thrown out of the group after its annexation of Crimea in 2014.

A senior US official said this week that Trump and Macron agreed that President Vladimir Putin should be invited to the summit when it is held in the United States next year.

Macron, however, said this week that it would be a “strategic error” to let Russia back in before the Ukraine issue is settled. Britain and Germany have also expressed reservations.

But when Trump hosts the meeting next year – perhaps at one of his own resorts in the US – he will have greater latitude to set the guest list.

“We know that Trump doesn’t like international institutions – so will he cancel the G7 summit next year?” asked Nicholas Dungan of the Atlantic Council and of Sciences Po, a prestigious university in France.

“No, he will not cancel. By inviting Putin he will poke a stick in the eye of the other G7 members, who will have to decide whether to boycott the G7 in the United States,” Dungan predicted.

Another area of disagreement in France could be over climate change, which Trump has branded a Chinese hoax. The President created a fracture with Europe by pulling out of the Paris climate accord, and he didn’t attend a meeting on the issue at Canada’s G7.

Boris Johnson’s balancing act

Trump could also anger leaders like Macron and German Chancellor Angela Merkel with his outspoken support for Brexit and open hostility to the European Union.

He will hold his first meeting with Boris Johnson since the new British Prime Minister took office, and the President has been goading him to pull Britain out of the EU without a deal with the bloc on October 31.

National security adviser John Bolton swung through London recently and expressed firm US support for the trade deal Britain will need with Washington outside the EU.

Bolton declared that he and Trump were “leavers before there were leavers” and slammed the leadership of the European Union and its attitude toward its people.

“The fashion in the European Union: When the people vote the wrong way from the way the elites want to go, it’s to make the peasants vote again and again until they get it right,” he said.

European leaders fear that a no-deal or “hard Brexit” and resulting chaos at ports and border crossings will damage their economies – though not as much as Britain’s.

They are also bewildered by Trump’s attitude towards the bloc the US has long supported as a bulwark of post-World War II stability.

Trump has made a great play of his friendship with Johnson, recently calling him “Britain Trump.” There are stylistic similarities between the two men: Both have barnstorming personalities, decry details and often suffer from foot-in-mouth disease.

But the meeting with Trump puts Johnson in a difficult position, not least because the President is unpopular in the UK.

The Prime Minister – over whom Trump has significant leverage owing to Britain’s need for a trade deal – must work out how to position himself between the US and European leaders and avoid alienating the easy-to-anger Trump.

While they agree on Brexit, Johnson and Trump have big differences, including over climate change and the Iran nuclear deal. Trump’s White House has been aggressively trying to weaken European influence by peeling Britain away from the EU.

Conley pointed out that there was little public support for big “sea change positions” in Britain on Iran, China and climate change.

Johnson “himself is already in election mode, and he has to think about his domestic audience as well. So I think there’s a little limitation to this.”

CNN’s Kylie Attwood contributed to this story.