He’s written a letter berating Canada over its failure to meet the alliance’s defence spending target and, more recently, used a rally as a chance to complain that Americans are “schmucks that are paying for the whole thing,” and he doesn’t plan to let that stand.
But if Trump, who meets with allies including Prime Minister Justin Trudeau at this week’s summit in Brussels, significantly weakens NATO, what will Canadians lose? How important is the North Atlantic Treaty Organization to Canada?
“In some ways, next to trade, Trump’s attitude to NATO and his policy toward the allies, including us, is our worst nightmare,” said Robert Bothwell, a professor of history and international affairs at the University of Toronto, via email.
“We need NATO, now more than ever. Russia is back, the U.S. is run by a populist charlatan and Russian dupe, and the Europeans are the only reed we have in this storm.”
The treaty has been a cornerstone of Canadian international security since it was signed in April 1949, said Roland Paris, a professor of international affairs at the University of Ottawa. It was, and still is, a way to collectively defend the North Atlantic and Transatlantic community from terrorism, emerging threats and Russian aggression.
“It’s a means by which Canada and Europe cooperate to ensure their mutual security against common threats,” he said. “We’re strong in alliance.”
WATCH: Experts feel Trump will divide nations at NATO summit
Without NATO, Canada would likely be dragged into European conflict, said Elinor Sloan, a professor of international relations at Carleton University.
Already the security situation has deteriorated, she said. And while Canadian troops are in Latvia in a bid to beat back Russian pressure on Eastern Europe, Sloan said, “really, it comes down to the U.S. presence in Europe and right now that’s done through NATO.”
With NATO, she said, Canada is able to step “out from under the shadow of the U.S. elephant” and help guide discussions. Without it, Sloan said, Canada could be dragged into conflict with less of a voice.
“We would not be able to ignore growing acrimony amongst European countries,” she said, “but we wouldn’t have a voice… it would be just the United States working with Europe.”
A weakened NATO wouldn’t just be a problem in Europe, said Aurel Braun, a professor of international relations and political science at the University of Toronto.
“The truth of an alliance is to be able to do things collectively that you cannot do individually,” he said.
Canada has to contend not just with lengthy coastlines on three fronts, Braun said, but also with the reality of climate change opening the Arctic up to more navigation.
“We need to protect passage,” he said, “we need to protect our sovereignty.”
That’s not yet at risk, said Paris, as “American actions in NATO have been much more responsible than Trump’s language.”
WATCH: White House continues to apply pressure on NATO allies to spend more
While there’s a tendency to anticipate each NATO meeting as if it’s “the critical meeting of all time,” he said that’s rarely the reality.
“There could be some dramatic developments this week if Donald Trump questions the very value of NATO and then continues on to a meeting with (Russian President Vladimir) Putin where he embraces Putin with an unusual warmth,” Paris said.
But even if that happens, prompting people to question the value of a western alliance, he’s confident NATO can withstand the questioning.
“I don’t think the western alliance can sustain that kind of behaviour from a U.S. president for a long time but it almost certainly can for another two and-a-half years,” Paris said.
“The question is what happens beyond that.”
— with a file from The Canadian Press