The Arctic is under siege as never before. The Russians send submarines deep below the North Pole. The Americans dispatch surveillance planes to monitor new threats in the north. And Canada is now forced to scramble to defend territories it has ignored for too long. Global warming is turning the Far North into a resource hotspot. The fabled Northwest Passage could become a new super highway for cargo and cruise ships. And beneath the rapidly melting ice lies much of the world's undiscovered oil and gas reserves.