A coal plant spews out black smoke behind a road sign at the entrance to the miners' town of Barentsburg, on the Svalbard Archipelago, northern Norway, on May 7, 2022. JONATHAN NACKSTRAND/AFP VIA GETTY IMAGES

As the war in Ukraine approaches its two-year mark, some of the attention of U.S. officials and their NATO allies has been pulled toward another pressing issue: Russia's military buildup in the Arctic Circle. The expansion includes the recent unveiling of two nuclear submarines by Russian President Vladimir Putin, signaling a major strategic shift in the region.

Norway's Svalbard Archipelago, deep inside the Arctic Circle, is recognized as the world's northernmost permanent human settlement. Scientists say climate change is happening faster in the Arctic than anywhere else on the planet, and those changes are not just a concern for the Earth — they have also transformed the Arctic into a potential military flashpoint, and a new focus of the tension between Moscow and the U.S. and its NATO allies.

The melting polar ice caps have opened new shipping routes and exposed untapped reserves of oil and natural gas. Russia is testing hypersonic missiles, capable of evading American defenses, in the Arctic. This August, a joint Russian and Chinese military flotilla was observed patrolling waters near Alaska.

There's concern over the fact that Russia now operates a third more Arctic military bases than the U.S. and NATO combined, suggesting a strategic advantage in the region. Experts say the West's military footprint in the Arctic lags about 10 years behind Russia's. Norway, a key NATO member, is among the nations closely monitoring these developments, due to its proximity to Russia's military installations.

Former deputy head of Norway's intelligence agency Hedvig Moe helped her country catch a suspected Russian spy last year who had been posing as a researcher at Norway's Arctic University. This year, 15 Russian diplomats were expelled by Norway amid accusations of espionage.

"The northern part of Norway, including Svalbard, is particularly important to Russia because they have nuclear submarines stationed in Kola, which is very close to the Norwegian border. Those nuclear submarines need a clear line to get out from Kola toward the U.S., to be able to launch their nuclear weapons in case of a conflict with the U.S," explained Moe. "We all hope we're not going to end up in that situation, but it's part of the defense that Russia has."

Russia already has a toe-hold on Svalbard, thanks to a century-old treaty that allows Russian citizens to live there — visa-free, in a NATO member country. Barentsburg is a Russian coal-mining settlement with its own school, a giant Russian consulate and, as of earlier this year, a Russian military-style parade, all on Norwegian territory.

Dimitri Negrutsa told CBS News he was in charge of public relations for the Russian enclave. He admitted that, to his knowledge, the coal mines there weren't really profitable. But when CBS News noted to him that such facts could help fuel credibility of accusations that Barentsburg was, in fact, being used as a base for Russian espionage, he was immediately dismissive.

"I can give you a very simple answer, that it's not," he said.

Moe told CBS News she couldn't get into "specifics," but said "Svalbard is super important to Russia, so might be important to intelligence services as well."

The U.S. Department of Defense, while recognizing the increase in Russian Arctic bases, stressed that this alone does not reflect the entire scope of military capabilities of either nation.

In a statement to CBS News, Lt. Col. Devin T. Robinson, spokesperson for the Pentagon's Arctic and Global Resilience policy team, said the U.S. military "remains ready to respond to any aggression against the United States or our Allies," and that it was continually "tracking the growing cooperation between" Russia and China in the region.

"The Arctic presents unique challenges to the Department," Robinson acknowledged, "but we believe we have the right strategic approach, and a strong network of allies and partners, to navigate the changing geophysical and geopolitical environment in the region."

He noted, specifically, Finland and Sweden recently making "the historic decision to join NATO."

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