The ability to sustain persistent airborne maritime surveillance has become a structural determinant of maritime security in the Euro-Atlantic theatre. Modern naval operations depend on a layered system in which maritime patrol aircraft provide the wide-area sensing and coordination layer linking surface vessels, submarines, seabed sensors, and coastal command structures. When the availability of these aircraft falls below the level required to maintain persistent coverage, the operational effect appears immediately as gaps in maritime domain awareness. Those gaps shorten warning time, weaken submarine tracking chains, and increase the probability that hostile activity near undersea infrastructure will remain undetected long enough to produce strategic effects. In a security environment where energy cables, telecommunications links, and seabed infrastructure underpin economic and military resilience, the availability of maritime patrol aircraft is therefore not a niche aviation issue but a central element of deterrence and infrastructure protection.