Bergen, Norway — In the frigid waters off the coast of Norway, America’s NATO allies scour the depths for clandestine Russian activity.

The stretch of ocean, viewed as a gateway to the Arctic, is where Europe’s high north meets the Russian high north, home to the Kremlin’s Northern Fleet. 

Nuclear-armed Russian submarines are dispatched regularly from the vast naval base on the country’s freezing Kola peninsula, slipping silently beneath the waves before heading into the North Atlantic.  

CBS News joined the crew of a NATO warship taking part in drills aimed at detecting, tracking and — if necessary — taking out these subs before they pass through the narrow gap between Greenland, Iceland and the U.K., and onward to the United States’ eastern seaboard.  

If a war were to break out between Russia and the U.S. and its NATO allies, the area would become a strategic chokepoint.

Commanders see Operation Arctic Dolphin — an exercise involving ships, submarines and aircraft from Spain, Germany, France, the U.K. and many other nations — as essential to maintaining cohesion in a military alliance that has endured for 75 years.

“Norway has the great advantage of being a part of such a huge alliance,” said Commodore Kyrre Haugen, commander of the Norwegian Fleet overseeing Arctic Dolphin. “But every nation is taking advantage of being a part of something that is bigger than themselves.”

The commander said Norway has operated in the Arctic since the Cold War, and the “special focus” on the region now highlights how crucial it is to the security of both Europe and the U.S.

“Those missiles can attack Europe, can attack America by being deployed in the deep seas, all into the Atlantic,” he said, referring to Russia’s arsenal.

The NATO drill is just one aspect of a race to secure a region that has become a “front line for strategic competition,” according to U.S. Air Force General Alexus Grynkewich, NATO’s Supreme Allied Commander in Europe. 

Russia’s already using the Arctic as a testing ground for its hypersonic missiles, designed to evade U.S. air defenses. 

But threats to regional stability have also emerged closer to home.   

President Trump angered NATO partners by repeatedly insisting the U.S. needed to take ownership of Greenland — and by threatening last month to impose tariffs on allies if they didn’t comply. 

He backed off that threat, announcing a still-vaguely defined “ultimate long-term deal” with America’s NATO allies on Greenland, but he also routinely lambasts those allies, accusing them of not spending enough on their own defense. 

Undeniably, the alliance is playing catch-up in the Arctic and the high north. Seven of the eight Arctic states are NATO Allies. Yet Russia, with more than half the Arctic coastline in its territory, has almost as many permanently-manned bases in the region as all NATO members combined.

On the bridge of the Spanish frigate ESPS Almirante Juan de Borbon, the commander defended to CBS News the contribution to NATO by Spain, which Mr. Trump recently accused of not being “loyal” to the alliance.

“I’m not going to dig into political dynamics,” said Rear Admiral Joaquín Ruiz Escagedo, before gesturing to the young naval officers busy in front of maps and radar screens. “But I would say the contribution of Spain, you can see here.”

Escagedo said the country has “a lot of capabilities,” and is committed to NATO’s collective defense principle.

“We cannot be isolated. The power of NATO is the unity,” he said. “That’s the success of NATO for decades.”

That unity is about to be tested with a new mission. 

NATO planning new Arctic Sentry mission for “enhanced vigilance” in the far north

A spokesperson for Gen. Grynkewich, NATO’s American commander in Europe, confirmed to CBS News that planning is underway for a mission in the Arctic region.  

Arctic Sentry will be an “enhanced vigilance activity to even further strengthen NATO’s posture in the Arctic and High North.”

The spokesperson told CBS News that planning for the new mission has “only just begun, but details will follow in due course.”

The possibility of an Arctic Sentry mission was first mentioned by Britain’s top diplomat last month, as an element of the negotiations that resolved Mr. Trump’s standoff with Europe over the fate of Greenland. 

Foreign Secretary Yvette Cooper said the U.K. had proposed working “through NATO on a new Arctic sentry, which is similar to what we already have through NATO — a Baltic Sentry and an Eastern Sentry,” referring to existing regional security partnerships among NATO allies.

“This is now going to be a focus of work through NATO, with different Arctic countries coming together and supported by other NATO countries on how we do that shared security,” she told CBS News’ partner network BBC News on Jan. 22.