How much would it matter if RMS Queen Mary were sunk by a U-boat in early 1942?
Short answerIt would force costly replacement troop lift and scrutiny of Atlantic routing and intelligence, but the Allies would adapt rather than lose the war.
NotesQueen Mary is credited with more than 800,000 troop journeys during World War II, mostly between America and Britain. Those journeys represent lift that other ships would have to replace if the liner were lost in early 1942. More Liberty ships are suggested as one possible response, although no precise replacement programme is worked out. The expectation is a substantial disruption that the Allies would eventually work around. A successful submarine attack would also prompt scrutiny of the other liners and their intelligence support, since high speed and routes informed by Enigma decrypts were intended to keep them clear of U-boats.