Alaska has been an object of fascination, exploration, and exploitation for nearly two centuries, but its most inhospitable reaches – those that creep toward the Arctic Circle mile by frozen mile – have managed to hold on to their secrets for a very long time. Ice, plunging temperatures, and brutal tundras have kept outsiders at bay. That’s all shifting now: Climate change has warmed the Arctic’s formidable barriers, sparking a geopolitical and commercial footrace. Liam Denning is an energy and climate columnist for Bloomberg Opinion who has repeatedly traveled to the Arctic to report on the military, oil and gas, and fisheries.