From the towering waves between Newfoundland and Greenland to the icebound coasts of Svalbard- Canadian, Danish, and Norwegian naval vessels have maintained patrols for decades. But when those grey hulls take a decade to build and serve for nearly half a century, how do these navies prepare for unexpected geopolitical threats? Fjords Deep and Oceans Blue: Norwegian, Danish, and Canadian Seapower 1945-2025 is a study of peacetime sea power and argues for the interdependence of institutional and compulsive power at sea. Using the introduction of the 200 nautical mile Exclusive Economic Zone as a potential driver of major change, Timothy Hiu-Tung Choi looks at how the naval force structures and the operations of the three smaller Arctic navies have evolved through the Cold War to present. Featuring field research on board active patrol ships and multilingual sources, Fjords Deep and Oceans Blue embraces the details of how these forces tactically implement their strategic directions. Its temporal scope accounts for the multidecade lifespans of naval vessels from their initial conception through to end of life, unveiling insights into the trade-offs these navies encounter as they balance military and constabulary roles in the face of uncertainty.