The threat of a review was yet another surprise for European allies and Canada as they learn to deal with an increasingly unpredictable ally. U.S. officials and senior military officers had promised to coordinate closely with the Europeans as America draws down.

Just weeks ago, the Trump administration said that it would no longer provide as much military support should any NATO member come under attack, leaving them scrambling to find equipment to plug any gaps.

In recent months, U.S. President Donald Trump and the Pentagon have sent conflicting signals about whether America is reducing or increasing its military footprint in Europe, as well as threatening to annex Greenland, a semiautonomous island that is part of ally Denmark.

“This will be a real review. It will be designed to ensure that NATO is moving fast and irreversibly toward Europe leading, stepping up to take primary responsibility for the defense of Europe,” Hegseth told his NATO counterparts. “It’s a review that some countries will fail and others will pass with flying colors.”

A public dressing down over base use, gender and migration

In a fiery speech at NATO headquarters in Brussels, Hegseth also lambasted European allies for failing to provide U.S. forces access to bases in Europe to launch attacks on Iran, calling it “shameful.”

“These allies, they put America’s sons and daughters, our sons and daughters, at risk by denying them the predictable access, basing and overflight that never should have been in question at all,” he said. The review would also assess whether the U.S. has full access and overflight “when we need it.”

While defense ministers and military officers sat in silence, Hegseth railed against migration and gender equality policies in Europe, in remarks reminiscent to those of Vice President JD Vance in February last year that angered many Europeans.

“Instead of tanks and fighters and air defenses, the focus has been on gender equity and climate change and defense austerity. Europe’s borders flew wide open, welfare states expanded, defense budgets cratered, along with Europe’s belief in itself and its civilization,” Hegseth said.

Hegseth’s comments largely mischaracterized European policies today. On defense, European allies and Canada have launched an unprecedented effort to boost defense spending and expand their armed forces. NATO Secretary-General Mark Rutte noted on Thursday that they spent $90 billion more on defense last year, a 20% increase over 2024. And while Europe accepted large numbers of migrants and asylum seekers more than a decade ago, most countries have tightened their borders since.

It does not augur well for a summit of NATO leaders in Turkey on July 7-8.

A rare and short visit to NATO

It was a rare visit to NATO by Hegseth, his first this year after skipping a meeting in February. The Pentagon chief did not stay long on Thursday either, leaving well before this gathering was over and hours before Ukrainian President Volodymyr Zelenskyy was due to press allies for more weapons for his country.

Speaking to reporters at Brussels airport before flying home, Hegseth said, “It was great to hear country after country say, ‘We’re going to meet our target. We’re going to meet our target.’ There are still a few outliers, and we will be clear with them as we do this review.”

NATO’s supreme allied commander, an American, is working on backup plans to defend Europe after the U.S. signaled on June 3 that it would no longer supply an aircraft carrier and support ships, aerial refueling planes and dozens of fighter jets, among other military assets, in a crisis.

The Trump administration insists that it needs to be able to plan for two simultaneous conflicts and wants more military resources at hand should it clash with China in the Indo-Pacific region.

Under NATO’s collective security guarantee – Article 5 of its founding treaty – the 32 allies pledge that an attack on one of them will be considered an attack on all. It does not oblige them to provide military support, although many likely would.

In essence, the United States is scaling back how it might help should an ally trigger Article 5.

US nuclear weapons will stay

The U.S. has by far NATO’s biggest armed forces. It does not intend to withdraw its nuclear weapons in Europe, which are key to NATO’s deterrence. To underscore that point, NATO’s Nuclear Planning Group issued its first statement in 19 years after Thursday’s meeting.

In the statement, it “recalled that the strategic nuclear forces of the Alliance remain the supreme guarantee of Allied security and underpin NATO’s extended deterrence architecture.”

The ministers “agreed to continue enhancing NATO’s nuclear deterrence mission by modernizing NATO’s nuclear capabilities, strengthening its nuclear planning capacity, and adapting to achieve its security interests.”

Rutte played down the impact of the U.S. decision, saying that the NATO Force Model – the system for organizing what forces member countries will provide commanders in times of peace, crisis or conflict – is just “a planning tool,” and not a reflection of what would actually happen.

“If war breaks out, we will all max out what we need to do to make sure we can fight the war,” Rutte told reporters. “In the planning phase, it is important to know what we can count on. What is in theory there.”

He said that some European countries “are already backfilling a lot of those resources, in other cases, we are nearly there, and there is still areas where we need more work to do. So we are in a good place.”