Thousands of troops and the latest in American military hardware will soon descend on Alaska for war games between branches of the armed forces. “Northern Edge” is a biennial, large-scale exercise held in May . And planners are looking ahead at the next decade of maneuvers in Alaska’s skies and waters. Northern Edge 2021 will span from the Aleutians to Fairbanks to Juneau, in the air, and on the water in the Gulf of Alaska. “We’re going to have 240 joint aircraft, so that’s aircraft from the Air