David Wragg suggests that earlier escort-carrier conversions could have helped end the European war up to a year sooner. Better convoy protection would have saved merchant ships, cargoes, and lives, but an earlier Allied return to France still depended on American entry, the buildup of forces, suitable weather, and amphibious shipping. The principal constraint identified for D-Day is the construction of that amphibious shipping, so faster accumulation of supplies alone does not establish an earlier invasion date. If D-Day remained on the same timetable, an earlier German defeat would need another explanation. Greater pressure on the U-boat campaign might also have encouraged Germany to develop the Type XXI sooner.
Notable Point · 1:37:28-1:40:03
Why earlier escort carriers would not automatically end the war
Saving more merchant ships in 1942 would have helped greatly, but it does not by itself move the invasion timetable or prove the war ends a year earlier.