The prime minister, Mark Carney, has admitted that he has already made plans for something once thought unthinkable: a US invasion. He told the New York Times that the danger is small and the chance very slight, but that his duty compels him to weigh every possibility as the ties between the two nations undergo a fresh arrangement under the Donald Trump administration.
“That’s just risk management,” Carney said.
Canada is now openly preparing for a possible American invasion, with war-gaming underway based on Trump’s global tariffs and his repeated desire to make Canada the 51st state. In 2025, the US president said it was “highly unlikely” that the US would ever use force against Canada. He went on to say that he would keep applying economic pressures instead, to gain political aims.
“President Trump has done more than anyone to protect the great people of Canada,” the White House told the BBC in a statement this week.
Military Experts Agree It Is a Long Shot
BBC military experts say an invasion is unlikely, citing the extensive defence cooperation between the two nations. A former Royal Canadian Air Force officer with 34 years of service, who held several senior posts, told the broadcaster that a war between Canada and the US would be complicated and almost difficult to imagine.
“I was involved in military operations for my whole career, and we never considered the possibility that there would be a military attack coming from US territory,” he told the BBC.
Coates pointed out that Canada and the US work together on military defence in several ways:
- Both nations belong to the north Atlantic defence alliance, which requires members to come to the aid of a fellow member-nation if it is attacked.
- They carry out joint Arctic defence operations under the North American Aerospace Defence Command (NORAD).
- They often exchange intelligence.
Coates stated that if the United States were to launch an attack on Canada, it would likely start through stealthier methods than a direct armed assault, such as cyberwarfare.
A History of Resistance
The two nations were not always the best of friends, yet Canada and the US became natural allies during the latter part of the 20th Century, with strong economic, military and cultural ties binding them together. The relationship was not always so close.
Tim Foran, a researcher with the Canadian War Museum, said a key part of Canada’s identity comes from resisting US expansionism during the 18th and 19th Centuries.
“Fear of the United States is foundational to the political project that is Canada,” he said.
A union of British North American colonies that stayed faithful to the British Crown gave rise to Canada, while the colonies now known as the US broke away from it. Prior to Canada’s creation, the US had tried to take over British North American colonies, seizing Montreal in 1775, and came close to capturing Quebec City.
The Americans repeatedly invaded what was then called Upper Canada, Lower Canada and the maritime colonies during the war of 1812, but the conflict ended in a deadlock. In response to those invasions, British forces famously set fire to the White House.
Great Britain and its Royal Navy were depended upon by the colonies that later became Canada for their defence, Foran said. He also noted that indigenous peoples served as generals in major battles.
After World War I, Canada considered going to war against the United States due to that nation’s rising strength and standing. The country drew up a plan that depended on covert visits to border towns by Canadian army generals. These officers traveled incognito as vacationers, taking pictures of bridges and roads for information purposes. They also engaged with local inhabitants to gain a fuller sense of their foe.
Andrew Burtch, a researcher with the Canadian War Museum who specializes in Canada in the 20th Century, said a war was an unlikely prospect at the time. Even so, the Canadians were determined to be ready.
“That’s part of what militaries do,” he said. “They envisage all sorts of different scenarios.”
What Canadians Think
Canadians appear to be concerned about this matter. A January Leger poll came out after the US took Nicolás Maduro in Venezuela, showing that more than 30% of those surveyed thought an American invasion was likely.
The Model That Shaped the Planning
Matthew Schmidt, an associate professor of national security at the University of New Haven in Connecticut, argued that the simple fact that Canadians are planning for a US invasion shows how much the world has changed. He also noted that Canadian leaders need to consider whether they want to keep cooperating so closely with the American military, a bond that could give the US useful information if it ever wished to hurt Canada.
“It’s really doing harm to relationships with the United States, and there’s a certain amount of legitimate fear,” he said.
He suggested that Americans may dismiss Trump’s remarks about turning Canada into the 51st state as empty talk, while Canadians are taking them seriously enough to prepare for their own defense if necessary.
So what would it be like if it happened?
A war’s opening round can be brief. A model employed by the Canadian military, as described by the Globe and Mail earlier this year, suggests that a US strike would leave Canada’s strategic positions overwhelmed within a week. The country’s armed forces would soon find themselves outnumbered, and would likely need to adopt guerrilla-style tactics in an effort to hold back their adversary.
The paper said in January that France and Britain were expected to supply both protection and aid for Canada, drawing on the testimony of senior government officials.
A Canadian plan for an American attack is being called the first of its kind in a century, according to a theoretical model. Coates described the modelling as modest by military standards.
The person stated that Canada trailed its Nato allies when it came to having a response plan ready for any ground invasion, and that it was now playing catch-up.
What the Poll Says
The Leger poll found that over 30% of Canadians believed a US invasion was likely after the US captured Nicolás Maduro in Venezuela. The figure reflects the tension in the relationship rather than a prediction of war.
A Pattern of Preparations
Canada has admitted to planning for an attack from the world’s largest economy, following a pattern of preparations that began during the Trump administration. This public acknowledgment signals that the relationship between the two countries has fundamentally shifted.
A sizable share of the public considers the danger real enough to warrant worry, according to the poll results. More than 30% of Canadians thought a US invasion was probable following the US capture of Nicolás Maduro in Venezuela.
What This Means for the Relationship
Carney’s admission is notable precisely because it is unusual. A sitting prime minister publicly acknowledging the need to plan for an attack from the world’s largest economy is a signal that the relationship has changed in a fundamental way.
The White House’s statement that “President Trump has done more than anyone to protect the great people of Canada” shows how the two sides read the same events in opposite ways. Canadians view a president who has warned of changing the map of North America by force. The United States sees a leader who has tightened ties by concentrating on common interests.
Polling data reveals that Canadians are not treating these statements as mere empty words. Instead, over 30% of those surveyed believed a US invasion was likely, which indicates the public is paying close attention to the diplomatic signals being sent.
A Catch-Up Moment
The fact that Canada is now scrambling to catch up with its Nato allies on plans for a ground invasion speaks volumes about how threat assessments have changed. Even so, the real chance of such an attack staying low, as Coates notes.
How a war might play out is painted in grim terms by a model adopted by Canada’s military: a swift breakdown of strategic positions giving way to guerrilla warfare.
The Bottom Line
Carney’s acknowledgment marks a sobering turning point for Canadian diplomacy. It accepts that Canada’s ties with the US have moved into a new phase, one where the unthinkable must now be taken seriously.
The experts speaking to the BBC stick to the same view: an invasion remains unlikely. The very fact that Canada is getting ready for such an event shows how seriously the threat is being treated.
Polling data supports this point: over 30% of Canadians think a US invasion is likely, reflecting public worry rather than any prediction of conflict.
| Event | Date | Context |
|---|---|---|
| Trump’s 2025 statement | 2025 | Highly unlikely to use force against Canada |
| Maduro capture in Venezuela | January | Leger poll finds over 30% of Canadians believe invasion is likely |
| Carney’s admission | Last week | Prepared for all possibilities, including US invasion |
| White House statement | This week | Protects “the great people of Canada” |
Planning for an American attack is something Canada has not done in over a century, according to its military model. The change marks a notable alteration in how Canada assumes conflict might unfold, even though the chance of invasion itself stays small.
Canada and the United States are seeing their relationship shift. The country is changing how it posts its forces, and people are watching closely to see what it means. The question on everyone’s mind is whether this is a short-term readjustment or the beginning of a long-term change in how the two nations regard one another.
The takeaway for now is straightforward: an outside chance still calls for a strategy.
Source material: “Why Canada is preparing for a (long shot) US invasion,” the BBC.
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