What problems would Atlantic convoys face if Bismarck survived her 1941 sortie?
Short answerOne successful raid would hurt a few convoys, but the greater problem would be a repaired Bismarck in France acting with Scharnhorst, Gneisenau, and Tirpitz and forcing Britain to disperse heavy covering forces.
NotesAn undamaged Bismarck might destroy or scatter one or two convoys before fuel and ammunition forced her home. If she reached a French port, Britain would have to keep enough ships and aircraft ready for a breakout while also watching Tirpitz in Norway. Repeated attacks on the French bases would intensify, and Britain might accelerate Vanguard or even resume a Lion-class completion to increase available heavy cover. After Scharnhorst and Gneisenau had already demonstrated the danger, a surviving Bismarck would also strengthen the political case for carriers, capital ships, and better Fleet Air Arm aircraft.