Sea control need not mean permanent, uncontested command of an ocean. An opponent may achieve sea denial for a time without making every transit impossible. NATO could concentrate escorts and aircraft to secure a route only for the period in which a convoy crosses it. The operational question is who can create the necessary degree of control at the place and time a mission requires.
Notable Point · 1:36:53-1:38:22
Sea control only has to last long enough for the mission
An opponent's sea-denial capability does not make control all-or-nothing because escorts and aircraft may only need to open a temporary corridor for a convoy.