PARIS • United States President Donald Trump's outburst after the Group of 7 (G-7) meeting in Canada raised questions over his commitment to his closest allies. Their next encounter could answer them.
Mr Trump is expected to attend the Nato summit from July 11 to 12 in Brussels, a gathering whose goal was to re-affirm the transatlantic partnership - and that was before Mr Trump withdrew from a G-7 statement on trade, insulted Canadian Prime Minister Justin Trudeau and accused Germany of freeloading on US military spending.
Mr Trump has been sparring with the US allies over trade for several months, but a refusal to reconfirm Washington's commitment to Nato would bring relations to a new low, said Mr Martin Quencez, senior programme officer at the German Marshall Fund of the US.
"So far, the Europeans have managed to separate security and trade issues with the US," said the Paris-based Mr Quencez. "If what happened at the G-7 repeats at Nato, then we are in a worrying situation."
Officials in two different European capitals have said there is not a "Plan B" to configure an international trade and defence system without US leadership or even involvement. One official said many European leaders are hoping November's midterm elections in the US will deliver a Democratic majority that would rein in the commander-in-chief.
"There's been such a succession of events with Trump that it's pretty clear the future of the Atlantic alliance is in doubt," said Mr Philippe Moreau Defarges, an adviser at the Paris-based French Institute for International Affairs. "But I don't see anyone in Europe with the talent or the confidence to push through the changes that would be necessary for a real European defence policy."
Greater defence cooperation among European Union members had been held up for years by Britain's reluctance to create anything that would compete or overlap with Nato. The British vote to leave the EU has removed one block to a more integrated defence policy, but plenty of others remain, such as members' widely varying military capabilities and policy objectives.
EU leaders last December agreed to a defence pact called Pesco, or Permanent Structured Cooperation, which at this stage is limited to 17 projects in areas such as marine surveillance. While hailed by the EU Commission as a major breakthrough, permanent joint military forces are a long way off.
The EU lacks capabilities such as a fifth-generation fighter jet, a carrier fleet and sufficient air transport to project power on a global scale. Indeed, few member states are willing to spend the sums required to develop such capabilities in the immediate future, limiting the bloc's clout and making it dependent on America's security umbrella.
German Chancellor Angela Merkel, in a television interview on Sunday, said Mr Trump "is right to a certain extent" when he criticised Berlin for spending only 1.3 per cent of economic output on defence, short of the 2 per cent guideline set by Nato. "We need to increase our defence budget," she said.
Mr Quencez said Dr Merkel has made similar promises with little to show for it. Mr Moreau Defarges said she is too weak politically to push through unpopular increases in military spending.
The US accounts for about three-quarters of the military spending of all 29 Nato members, according to the alliance.
Dr Jacques Attali, former head of the European Bank for Reconstruction and Development who has advised French presidents since the 1980s, said the recent blowup does not really change things.
"It doesn't matter because the G-7 communique didn't really say anything, it was devoid of real content," Dr Attali said on Monday on France2 television. "We have to keep dealing with this man who represents the most important country in the world."