The United States argues that, though the Canadian Islands are indeed very close to the narrow Northwest Passage, it should be agreed that it's an international seaway, similar to the internationally agreed open sea lanes, for example in the narrow straits of Molucca.
Overall, no one knows exactly how much mineral wealth, strategic advantage and even new warm-water fisheries profit may be produced by the great warming, but nations are jockeying for position to deal with it and take advantage of it.
"I would be surprised if this ended up leading to a shooting war," said Bookings' Antholis. "That said, these are the kinds of tensions that take up leaders' time and leaders often don't want to be bothered with."
In centuries past, such disputes might have meant war.
That may not seem likely now, but as global warming keeps opening these waters, it's producing new tensions among old friends.