A submarine snakes through a fjord in Norway alongside a British amphibious transport ship, as F-35 fighter jets roar overhead. NATO forces are gathered for a joint drill to repel a simulated invasion, albeit one where the enemy seems anything but theoretical.

President Vladimir Putin’s war in Ukraine may be raging thousands of kilometers to the south, but in the remote Arctic there is a close watch on his military activities. It’s an increasingly important region for energy, trade and security, and one where Russia, the U.S., China and others are vying for greater control.

The extent of Arctic seabed resources is not well mapped but estimates suggest the region holds around one-fourth of the globe’s oil and natural gas resources, while its sea routes could shave days if not weeks off traditional commercial shipping passages.