The warning comes as Secretary of State Mike Pompeo prepares to attend a summit of the Arctic Council, the eight countries with territory in the region, and hopes to rally them to counter Chinese influence.
"We’ve committed to peace and sustainable economic developments [in the Arctic] for the long term, and we’re concerned about activities of other nations, including China, that do not share these same commitments," said a senior State Department official, speaking anonymously to brief reporters.
As in previous years, the congressionally mandated Pentagon report assesses China's military and security developments and how those fit in with the nation's long-term growth strategies in the Pacific. This year's report specifically highlights China's growing interest in the Arctic, which has alarmed countries with interests in that region.
In 2018, China published its first Arctic strategy, coining the phrase "Polar Silk Road" -- a reference to the ancient network of trade routes that connected China to the West. The strategy also declared that China is a "Near-Arctic State."
"There’s no such definition in the [Arctic] Council’s lexicon," the senior State Department official said. "There are Arctic states and there are non-Arctic states. The eight Arctic states conduct governance of the Arctic region, and we reject attempts by non-Arctic states to claim a role in this process."
According to the report, China's interest in the Arctic is multi-faceted but centers around a desire for access to natural resources and securing sea routes in that region. As the earth's temperature warms due to climate change, ice melt in the Arctic is opening up new shipping lanes, but the Pentagon warned that China's presence there could lead to the deployment of submarines "as a deterrent against nuclear attacks."
Assistant Secretary of Defense for Indo-Pacific Security Affairs Randall Schriver told reporters on Friday that the Pentagon will watch whether or not the Arctic "becomes an access point for safe harbor for [China's] strategic assets, such as ballistic missile-carrying submarines."
"It is a possibility in the future, and one to watch very closely," Schriver said.
Pompeo will push the Arctic Council countries to take action to address that concern, among others, and keep China out of any decision-making.
But he could be distracted by fighting within the Council over climate change. The Trump administration has moved to withdraw the U.S. from the Paris climate accord, but the other members have been pushing for language in a joint statement that would recognize the commitments they made to combat climate change in the historic accord. U.S. officials have tried to remove any of that language.
The State Department declined to comment on those discussions, but a second senior official told reporters, "When we don’t agree with our allies and friends, we talk with them about it directly. We engage them closely, and that’s what we’re doing in the Arctic Council."
The official denied that any fights over climate change would distract from the goal of unity against China's steps into the region.
Anne-Marie Brady, author of a book on China's role in the Arctic and executive editor of The Polar Journal, pointed out on Twitter that Chinese rulers have had Arctic ambitions for over half a century. Chairman of the People's Republic of China Mao Zedong set a goal of sending nuclear submarines to the Arctic back in 1959.
While China has yet to achieve that goal, it would have significant implications for global security, Brady said.
"If Chinese submarines armed with nuclear weapons were able to access the Arctic Ocean without detection, this would enhance China's nuclear deterrence, strengthen China's position in NE/SE Asia, would bolster China's position as a military power and global leader," she tweeted.
The deployment of submarines is only one piece of China's Arctic strategy.
Last year, China's Xuelong ice-breaking research vessel, a Ukrainian-built ship operated by the Chinese, completed its ninth Arctic expedition. And in September, China announced it would build its first domestic ice breaking research vessel, the Xuelong 2, which will be able to penetrate ice up to about five feet thick. The Xuelong 2 would also be the first polar research vessel that would be able to break through ice while moving forwards or backwards, the Pentagon said.
While China already has research stations in Iceland and Norway, the nation is looking to expand its footprint into Greenland with a satellite ground station, renovated airport, and mining operations. Those ambitions have alarmed Denmark -- as Greenland is a Danish territory -- with the Danes publicly expressed concerns with China's interest in the world's largest island.
And China’s icebreaker missions are not getting support from Russia, another country with major Arctic ambitions. Russia opposes all foreign icebreakers operating in the Northern Sea Route.