The U.S., Canada and Denmark held major exercises two months ago, and in an unprecedented move, the military chiefs of the seven main Arctic powers — Canada, the U.S., Russia, Iceland, Denmark, Sweden and Finland — are to gather at a Canadian military base in May to specifically discuss regional security issues.

None of this means a shooting war is likely at the North Pole any time soon. But as the number of workers and ships increases in the High North to exploit oil and gas reserves, so will the need for policing, border patrols and — if push comes to shove — military muscle to enforce rival claims.

The U.S. Geological Survey estimates that 13 percent of the world’s undiscovered oil and 30 percent of its untapped natural gas is in the Arctic.