Was US involvement in WW2 crucial to the Allied Victory?

Stalin said “Without American production the United Nations could never have won the war,” during the Tehran Conference. Just in terms of industrial outpost and how that effected other Allies logistics and war fighting the US was irreplaceable. The Soviets received 17.5 million tons of aid from the Allies and 94% originated in the US. Of the aid the Soviet received accounted for: Nearly 60% of aviation fuel, 33% of military vehicles (including 12% of their tanks and self-propelled guns), 53% of the ordinance used, 30% of military aircraft, and anywhere for 50 to 80% of their industrial and military grade metal and steel. The US also gave the USSR 4,478,116 tons of foodstuffs and a one complete tire plant from Ford. The US provide railway related material including 1911 steam locomotives, 66 Diesel locomotives, 9,920 flat cars, 1,000 dump cars, 120 tank cars, and 35 heavy machinery cars along with a large amount of wide gauge rail. This aid in conjunction with production using lend lease material would account for nearly 93% of all rail related production in the USSR during the war. Even if the US didn’t take part in any battle in Europe or help cripple German production from the air the European Area of Operations still would have need the US to help.

Admittedly the USSR fought and killed the vast majority of German forces during the war (80% or German KIA were on the Eastern Front). However the Western Allies still took care of the rest, help to cut off German access to elsewhere and dealt crippling blows to production and drained resources from the Eastern Front. Operation Overlord (D-Day) only hastened the War’s end, the Soviets would have taken Berlin regardless but later and with heavy losses on both sides (the Germans could reliable surrender to the US without much fear). In all probability the landings and Normandy and Western campaign most important contribution was in the post war period. What do you think would have happened to all of Germany or more of Europe if the Soviets had “liberated” it like most of Eastern Europe. More of Europe under a new repressive foreign occupation like the PACT nations. The Pacific Campaign was nearly all handled by American force of arms after the Japanese advance through much of the European colonies with little slowing them.