Why a U.S. attack on Greenland would mean the ‘end’ of NATO

As U.S. President Donald Trump continues to threaten annexing Greenland, experts are warning the future of the North Atlantic Treaty Organization (NATO) — of which Canada is a member — is at stake.

Hours before the foreign ministers of Greenland and Denmark were set to meet top U.S. officials in the White House on Wednesday, Trump took to his social media platform Truth Social to push for U.S. control over the island.

“NATO becomes far more formidable and effective with Greenland in the hands of the UNITED STATES,” Trump wrote. “Anything less than that is unacceptable.”

Greenland is an autonomous territory of the Kingdom of Denmark, which is a member of the NATO military alliance. Last week, Trump hinted at potential action.

“If we don’t do it the easy way we’re going to do it the hard way,” he said.

Article 5 is one of the core principles of the 76-year-old military alliance and states that “an armed attack against one NATO member shall be considered an attack against all members, and triggers an obligation for each member to come to its assistance.”

The only time the article has ever been invoked has been after the terrorist attacks of Sept. 11, 2001.

The alliance has never had to deal with one member attacking another.

“Although NATO has survived tensions between its members in the past, there is no precedent for an actual internal attack,” said Nicole Covey, a fellow at the Canadian Global Affairs Institute.

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“After all, there is this established norm that allies are not supposed to attack each other if they want to maintain any sort of positive tie,” she added.

It is unlikely that the alliance would survive if the U.S., the de facto leader of the alliance, attacks another member, said Gaëlle Rivard-Piché, executive director of the CDA Institute.

“I think if the United States attack a NATO ally, it’s going be the end of the alliance. I do not see how the alliance would survive such an event. I don’t foresee a military invasion, but who knows, right?” she said.

Since Trump has ratcheted up the rhetoric, several NATO allies, including Canada, have come out in support of Denmark and Greenland, with some European countries on Wednesday announcing they are sending troops to Greenland to bolster Arctic security.

While Prime Minister Mark Carney has said Gov. Gen. Mary Simon will visit at an unclear date, it’s not clear at this time whether any Canadian troops might be part of that effort.

Global News has reached out to the Canadian Forces.

But Carney has noted recently that NATO can provide security for the Danish territory as the alliance does for all members.

“We’re partners in NATO. It is a mutual defence alliance. We can provide that security. As NATO, we can provide security for all of NATO, Greenland included,” Prime Minister Carney said to reporters at the Canadian embassy in Paris last week.

“The future of Greenland is a decision for Greenland and Denmark exclusively — it’s their decision.”

The response by both NATO and EU leaders is “expected,” Covey said.

“Greenland is being threatened by the United States and it would damage the credibility of both the EU and NATO leadership if they did not openly support Greenland,” she said.

However, member states also have to walk the tightrope of not offending Trump, Rivard-Piché said.

“It’s the stick and the carrot, but their stick is not very big,” she said, adding that the U.S. still shoulders the single-largest share of the NATO budget.

According to the Atlantic Council, the U.S. spends $928 billion on its defence budget, nearly twice that of Europe and Canada combined.

For Canada and its allies, years of reliance on the U.S. has weakened their own defence capabilities for a scenario such as this, Rivard-Piché said.

“That was a warranted criticism towards Canada and the fact that we just didn’t invest as much in defence over the last few decades, but now we need to step up,” she said.

In June, Canada joined other NATO countries in pledging five per cent of its budget on defence spending by 2035. A large segment of that is likely to go towards strengthening Canada’s capabilities in the Arctic, Rivard-Piché said.


“We are investing in our tech capabilities to increase our all-domain situational awareness from the seabed to space. We’re investing in advanced technology and underwater technology, so that we can actually monitor the region and know what’s happening,” she said.

Denmark has said Trump’s claim of imminent threats against Greenland from Russia and China’s are not accurate.

“Saying that the region is crawling with Chinese and Russian ships is just not reflective of the reality,” Rivard-Piché said.

The possibility of a military confrontation in Greenland is “extremely remote” but “not zero,” Covey said.

“Rationally, a military confrontation in Greenland between NATO allies should be unthinkable, but the Trump administration has already demonstrated that they are willing to act in an unpredictable manner,” she said.

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