Canada's icebreaker pact looked great until Trump starting threatening the Arctic

U.S. President Donald Trump's threats to Greenland, and the claims of continental hegemony contained in the new U.S. national security strategy, have awoken Canadians to the threat to their own Arctic sovereignty.

But Canada is still assisting the Americans in developing the very technology that could enable them to one day seize control of all or part of Canada's Arctic archipelago.

Canadian co-operation and design is central to the construction of a new fleet of ships that the U.S. intends to use to strengthen its presence in the regions surrounding the North Pole.

That new fleet will enter service under a new national security strategy that claims the right to demand access to all regions of the Western Hemisphere.

"DoW [Department of War] will therefore provide the president with credible options to guarantee U.S. military and commercial access to key terrain from the Arctic to South America, especially Greenland, the Gulf of America and the Panama Canal," reads the document. "We will ensure that the Monroe Doctrine is upheld in our time."

The current state of play between the U.S. and Canada in the High Arctic is governed by informal agreements reached following the last sovereignty dispute in 1985.

In that year the U.S. Coast Guard heavy icebreaker USCGC Polar Sea sailed from Greenland to the Chukchi Sea through the Northwest Passage. The U.S. government did not seek permission from Canada, but rather merely gave notification, in keeping with its long-held rejection of Canada's claims over the passage.

(The distance between Arctic islands often exceeds the standard 12 nautical miles considered to be a nation's territorial waters. Therefore, Canada's claim that the channels between the islands are "internal waters" is questioned by other countries.)

The voyage provoked considerable furor in Canada, which the U.S. government sought to mollify by allowing Canadian observers on board.

Two years after the passage of the Polar Sea, the U.S. quietly agreed that it would seek Canadian permission for future voyages, without recognizing the Canadian claim. That situation continues today.

As Brian Mulroney noted at the time, "One of the great ironies of the position taken by the United States, if followed to its logical conclusion, is that it could lead to much further freedom of navigation in the Arctic for the Soviets."

That's because if the U.S. insists the Northwest Passage is an international waterway, it risks throwing it open to the whole world, says Rob Huebert, an expert in Arctic sovereignty and security at the University of Calgary.

"In whose mind would that be more secure from an American perspective?" he said.

Those considerations could persuade the U.S. to leave the status quo in the passage alone.