I suppose it might have hampered the Soviet war effort to the extent that the western allies would have been able to capture all of Germany. Whether they would have done so, or held it, I'm not sure, as that would have left the USSR with no buffer and heightened tensions above what they actually were in the Cold War.
I agree with HareBrain that it would have retarded the Soviet comeback by 1 or even 2 years, but the German high-water mark (Stalingrad) predates the major influx of aid. Trucks are the biggie - they primarily served to enhance the Soviet mechanised corps that tore the front apart in 1944, at last giving them a logistical 'tail' and increasing their operational endurance. If The Soviets are slow off the mark in late 43/44, then that gives the Germans time to bolster the West pre-Normandy. The Germans still lose big, unless Hitler lets his Field Marshalls fight unfettered (eventual Allied victory but take a lot more casualties), but it would slow the advance through France to a crawl.
But with the Russians on the ropes , the German can redirect military assets to both Salerno and Normandy. This could potentially enable them to block the landings at both those places thus keep allies off the Continent for lander period of time . That might give time to further refine p some of their super weapons like the V2 and Jet fighters. The war drags on till 1947 or 48 and by that time the US has amassed \a stockpile atom bombs and starts targeting German cities.
At beginning of The Battle of Britain, the German Luftwaffe was the most powerful Air Force in the world , Fighter Command and the RAF severely mauled the Luftwaffe , costing them 3000 of thei best pilots and aircrews . That was slow beginning go the end of the Luftwaffe which never real recovered. The Germans made lots mistakes with regard to Russia , the biggest of which was invading them in the first place. Russia bled Wehrmacht dry. Russia swallowed men and equipmnet and resourcesNope, the German logistic chain had essentially broken down by the end of 1941 in Russia. It took a superhuman effort and a still disorganised enemy to attempt Case Blue and they failed on the River Volga and Stalingrad. As reiver points out that high water mark of November 1942 predates most of the aid.
Thus the Germans, smarting from the defeat at Stalingrad would still have to commit to a summer offensive against the Russians in 1943. So they attempt Kursk - which you note, is not a grand strategic operations to take vast amounts of Russia, but an opertion to merely reduce a salient in the Russian line. The German army by this stage had more or less spent its ability to go on the strategic offensive. And this too was a failure and they went onto the defensive.
I don't think Russia would have been on the ropes, as you say.
When 1944 comes around, the Battle for the Atlantic had been won and the Luftwaffe was effectively smashed. Yes, the Germans try their best to crush Normandy, but the air superiority and Western Allies logistics and numbers are too great. Add to this the inevitable collapse of Army Group Centre by the Russians in Bagration.
Now at this point, perhaps if there had been no aid, there might have been an effect, as this may have hampered the Soviet armies in this operation and slowed them down in their successes. But I don't think it would have added another year to the war.
Also, Baylor, why do you keep going on about these "Wonder" weapons . They weren't.
The V2 wasn't going to help them militarily and therefore essentially a waste of time and resources. The jet fighters they produced were good, but also unreliable and fuel guzzlers. But the main problem that the Luftwaffe wasn't planes, it was that they weren't producing enough pilots, or they weren't living long enough to maintain a deep pool of experienced pilots.
The British also gave us access to Frank Whittles jet engine technology .As an American who took history in the 60s, this is an embarrassing question. I remember a question on a test, "What General said 'Nuts!' to the Germans rather than surrender at the Battle of the Bulge?"
I didn't know the answer and thought it was a stupid question because of its unimportance.
The Russians hardly existed in my so called history of WWII. We rescued the British even though they gave us technology for RADAR and proximity fuses.
Nobody else matters in American history.
I only got C's in history because it was so obviously just propagandistic bullsh**. I don't really have a clue how much aid England and the US gave to the Russians. It probably wasn't until watching the History Channel that I had any idea how many Russians died in WWII.
LOLIt was Major-General Anthony McAuliffe that replied "Nuts!"
Nuts was from The Battle Of The Bulge. It was an important battle, largest and worst casualties for Americans in WWII, and it started out by catching the Americans completely by surprise and at first poorly positioned to do anything about it. Because of bad weather the US Air Force was unable to do very much. The situation changed radically when the weather cleared up.
I have a friend that maintains that the most important moments of WWII were the Battles of Khalkhin Gol across the summer of 1939. They completely removed the threat of a Japanese attack in the East, so that Soviet Russia only had to deal with Germany in the West... well... I say only....One thing to add for the Russian stability is the UK provided them intel. from Benchly Park with the Enigma machine, informing Stalin the Japanese had no intention of invading from China. So that provided Zhukov with almost a million troops to throw against Stalingrad.
The Eastern Front would have been a drawn out battle. Though Hitler constantly splitting his forces did not bode well.
The Germans had limited oil supply and their synthetic supply became a depleted fact with allied bombing. They would have taken the Caucasus and kept the war effort operational for perhaps another year. I also do not think their V weapons or Jets would have made a great impact. Too many irons in the fire was Hitler's problem - Bigger is Better.
Overall I see it as Russia able to hold on through manpower but the western allies would have taken Germany and there would not have been a Soviet Block.