Trump’s fight with NATO over Greenland ‘crossed a line that cannot be uncrossed,’ expert says

But despite those efforts, NATO’s credibility as a unified force under U.S. leadership has taken a huge hit over the past year as trust within the 32-nation military organization dissolved.

The rift has been most glaring over U.S. President Donald Trump’s repeated threats to seize Greenland, a semiautonomous territory of NATO ally Denmark. More recently, Trump’s disparaging remarks about his NATO allies’ troops in Afghanistan drew another outcry.

While the heat on Greenland has subsided for now, the infighting has seriously undercut the ability of the world’s biggest security alliance to deter adversaries, analysts say.

“The episode matters because it crossed a line that cannot be uncrossed,” Sophia Besch from the Carnegie Europe think tank said in a report on the Greenland crisis. “Even without force or sanctions, that breach weakens the alliance in a lasting way.”

The tensions haven’t gone unnoticed in Russia, NATO’s biggest threat.

Any deterrence of Russia relies on ensuring that President Vladimir Putin is convinced that NATO will retaliate should he expand his war beyond Ukraine. Right now, that does not seem to be the case.

“It’s a major upheaval for Europe, and we are watching it,” Russian Foreign Minister Sergey Lavrov noted last week.

Filling up the bucket

Criticized by U.S. leaders for decades over low defense spending, and lashed relentlessly under Trump, European allies and Canada agreed in July to significantly up their game and start investing 5% of their gross domestic product on defense.

The pledge was aimed at taking the whip out of Trump’s hand. The allies would spend as much of their economic output on core defense as the United States — around 3.5% of GDP — by 2035, plus a further 1.5% on security-related projects like upgrading bridges, air and seaports.

NATO Secretary-General Mark Rutte has hailed those pledges as a sign of NATO’s robust health and military might. He recently said that “fundamentally thanks to Donald J. Trump, NATO is stronger than it ever was.”

Though a big part of his job is to ensure that Trump does not pull the U.S. out of NATO, as Trump has occasionally threatened, his flattery of the American leader has sometimes raised concern. Rutte has pointedly refused to speak about the rift over Greenland.

Article 5 at stake

The North Atlantic Treaty Organization was formed in 1949 to counter the security threat posed by the Soviet Union during the Cold War, and its deterrence is underpinned by a strong American troop presence in Europe.

The alliance is built on the political pledge that an attack on one ally must be met with a response from them all — the collective security guarantee enshrined in Article 5 of its rule book.

It hinges on the belief that the territories of all 32 allies must remain inviolate. Trump’s designs on Greenland attack that very principle, even though Article 5 does not apply in internal disputes because it can only be triggered unanimously.

“Instead of strengthening our alliances, threats against Greenland and NATO are undermining America’s own interests,” two U.S. senators, Democrat Jeanne Shaheen and Republican Lisa Murkowski, wrote in a New York Times op-ed.

“Suggestions that the United States would seize or coerce allies to sell territory do not project strength. They signal unpredictability, weaken deterrence and hand our adversaries exactly what they want: proof that democratic alliances are fragile and unreliable,” they said.

Even before Trump escalated his threats to seize control of Greenland, his European allies were never entirely convinced that he would defend them should they come under attack.

Trump has said that he doesn’t believe the allies would help him either, and he recently drew more anger when he questioned the role of European and Canadian troops who fought and died alongside Americans in Afghanistan. The president later partially reversed his remarks.

In testimony to the Senate Foreign Relations Committee, U.S. Secretary of State Marco Rubio dismissed criticism that Trump has undermined the alliance.

“The stronger our partners are in NATO, the more flexibility the United States will have to secure our interests in different parts of the world,” he said. “That’s not an abandonment of NATO. That is a reality of the 21st century and a world that’s changing now.”

A Russia not easily deterred

Despite NATO’s talk of increased spending, Moscow seems undeterred. The EU’s foreign policy chief, Kaja Kallas, said this week that “it has become painfully clear that Russia will remain a major security threat for the long term.”

“We are fending off cyberattacks, sabotage against critical infrastructure, foreign interference and information manipulation, military intimidation, territorial threats and political meddling,” she said Wednesday.

Officials across Europe have reported acts of sabotage and mysterious drone flights over airports and military bases. Identifying the culprits is difficult, and Russia denies responsibility.

In a year-end address, Rutte warned that Europe is at imminent risk.

“Russia has brought war back to Europe, and we must be prepared for the scale of war our grandparents or great-grandparents endured,” he said.

Meanwhile in Russia, Lavrov said the dispute over Greenland heralded a “deep crisis” for NATO.

“It was hard to imagine before that such a thing could happen,” Lavrov told reporters, as he contemplated the possibility that “one NATO member is going to attack another NATO member.”

Russian state media mocked Europe’s “impotent rage” over Trump’s designs on Greenland, and Putin’s presidential envoy declared that “trans-Atlantic unity is over.”

Doubt about US troops

U.S. Defense Secretary Pete Hegseth is due to meet with his counterparts at NATO on Feb. 12. A year ago, he startled the allies by warning that America’s security priorities lie elsewhere and that Europe must look after itself now.

Security in the Arctic region, where Greenland lies, will be high on the agenda. It’s unclear whether Hegseth will announce a new drawdown of U.S. troops in Europe, who are central to NATO’s deterrence.

Lack of clarity about this has also fueled doubt about the U.S. commitment to its allies. In October, NATO learned that up to 1,500 American troops would be withdrawn from an area bordering Ukraine, angering ally Romania.

A report from the European Union Institute for Security Studies warned last week that although U.S. troops are unlikely to vanish overnight, doubts about U.S. commitment to European security means “the deterrence edifice becomes shakier.”

“Europe is being forced to confront a harsher reality,” wrote the authors, Veronica Anghel and Giuseppe Spatafora. “Adversaries start believing they can probe, sabotage and escalate without triggering a unified response.”