Both Canada and Denmark claim tiny Hans Island, a rocky outcrop ruled by ice and wind that lies between Greenland and Ellesmere Island. So when the Canadian defence minister, Bill Graham, landed there earlier this summer, the Danish government denounced the move as an 'occupation'.
Despite the formal diplomatic protest, Canada refused to back down. When the two countries drew an offshore boundary in 1973, they couldn't agree on the island, which is in a narrow channel of water, about 1,000 kilometres from the North Pole. The Danes have planted more than one flag there over the years, only to have them shredded by ferocious winds. The Canadians felt it was their turn.
But why now? The campaign for Hans Island, which measures all of 1.3 square kilometres, appears to be part of a broader effort to make sure the world knows that the Arctic archipelago is Canadian territory.
For years, experts have warned that Canada has not done enough to assert its sovereignty over the high Arctic islands and the Northwest Passage in particular. Global warming means that in the not-so-distant future, the fabled and usually ice-bound Northwest Passage could become a major shipping route between Asia and Europe. Melting ice, which could be catastrophic for the people and wildlife of the Arctic, could also make it more economically viable to look for undersea resources like oil and gas.
The Canadian government is hoping that increased activity in the area will protect its sovereignty. This month, the Canadian navy is on a mission to increase its presence in the north, with two vessels making several stops in the Arctic.
"We have new satellites that we're putting in place to patrol the Arctic, and we will be looking at the use of unmanned aerial vehicles. And we're looking at the way in which we can extend a radar protection which we have off the east and the west coast, to put it at the either end of the Northwest Passage so that we could control and ascertain what traffic is taking place there," Mr Graham said in a television interview.
In the past, Canada has not felt that it was necessary to have a continuous presence in the Arctic.
"These are new times and there will be new measures," he said.
Will it help? It's hard to say. The United States, for example, does not recognize that the Northwest Passage is under Canada's control. It argues the passage is an international waterway, open to foreign ships.
Then there is Denmark's claim to Hans Island. After Mr Graham landed on the island in July, the Danish government announced its own flag-planting mission, provided its navy vessel could get there before freeze up. It later called off the plan, saying it preferred to pursue its territorial claims through less icy diplomatic channels. Foreign ministers from the two countries are to discuss the turf war at the United Nations in September.
Canada claims the island was discovered by the British and ceded to Canada. The Danes say it is part of the ancestral territory of the Greenland Inuit (Greenland is part of Danish territory).
Some Canadian experts worry that Canada is risking too much in the fight for such a tiny island so far to the north of any potential shipping routes. They say if Canada loses on Hans Island, it will weaken its case on the Northwest Passage and other more crucial questions of Arctic sovereignty.