At most, the failure of D-Day would have slightly delayed the inevitable Soviet Victory. After the Soviet Victories at Stalingrad and Kursk in 1943, Germany had lost too much war material that it couldn’t replace anywhere near as quickly as the Soviets could and with the loss of the Romanian oilfields a couple of months after D-Day, the Germans lost their only major source of oil, which catastrophically limited their ability to move and provide air-cover....