Although strategic bombing requires that the enemy's industrial war capacity be neutralized, some Soviet factories were moved far out of reach of the Luftwaffe's bombers. Because the Luftwaffe's resources were needed to support the German army, the Luftwaffe became overstretched, and even victorious battles degraded Germany's air force due to attrition. By 1943, the Soviets were able to produce considerably more airplanes than their German rivals; for example, at Kursk, the Soviets had twice the number of airplanes that the Luftwaffe had. Utilizing overwhelming numerical superiority, Soviet forces were able to drive the Germans out of Soviet territory and take the war to Germany.