Dieppe Raid, France, 1942
It might be a mistake to call the Dieppe Raid a mistake. Fiasco seems a more appropriate term. The Royal Navy refused to commit capital ships with their heavy guns to provide gunfire support, mindful of German air superiority over the area of the raid. The Germans were aware of the coming attack, having been informed by French and British agents and spies. The troops committed were inadequate to the purpose of their mission, which was to seize a German port intact and hold it for a period of time determined by the tide tables, in order to discover if an invasion of France through a port was feasible at the time.
The landing force of just over 6,000 men, 5,000 of them Canadian (another 4,000 troops never made it ashore) lost over 3,600, a casualty rate of 60%. The Royal Navy lost a destroyer and 33 badly needed landing craft. The Royal Air Force lost over 100 aircraft, compared to under 50 losses by the opposing Luftwaffe. The landing troops were able to remain ashore for only about ten hours before the Royal Navy withdrew those they could, leaving the rest to be killed or become prisoners of war. Besides giving the Germans a tremendous propaganda opportunity, the Dieppe raid proved that the Allies were a long way from being ready to sustain an invasion of Europe, despite the continuing prodding of the Soviets that it was only a matter of resolve.