"What gradually swung the balance of resources back in the Allies' favour were two factors: the sheer speed and scale of American rearmament, which dwarfed anything that the Germans and Japanese, or even the British, had thought possible: and the swift revival of the Soviet economy after the mauling it received in 1941, when it sustained losses so severe that most pundits assumed the worst. Without the extraordinary exodus of Soviet machinery and labour from the war zones of the western Soviet Union to the harsh plains of Siberia, Stalin's armies would have been like the Tsar's in 1916, the soldiers in the second rank picking up the guns and boots of their dead vanguard as they scurried into battle. Against every expectation Soviet society worked feverishly to turn out the tanks and aircraft their soldiers needed. With only a quarter of the steel available to Germany, Soviet industry turned out more tanks, gun and planes than her German enemy throughout the war."