n the latest sign of the rising international political stakes in the Arctic, the top U.S. Coast Guard official has revealed a planned shift in American foreign policy from scientific research to "sovereignty" and "security presence" in Alaskan waters bordering Canadian and Russian territory.

And to underscore growing U.S. concerns over its aging polar icebreaking fleet and suspect capacity for Arctic surveillance, Homeland Security director Michael Chertoff slipped quietly into Alaska on Friday to assess the coast guard's northern operations.