But they loved our Studebaker trucks.
The Russians built arguably the best tank of WW 2. The T-34. Followed by the German Tigers and panthers, followed by the US Sherman.
If the British tanks were as reliable as their cars and motorcycles, I cannot imagine what Stalin was so critical of them for. /s
The American Shermans were faster to build, but nowhere near the engineering perfection of the German. But the speed at which they could be built or repaired and the volumes just knocked out the tigers.
Similarly the Russian ones were crude, but quickly built
40% of the tanks that the Soviets used to stop the Germans at Moscow came from Britain. That fact has been an embarrassment for them.
What did he think about the P-39 fighters he got from the US?
After World War I, the victors dismantled the vaunted German army, reducing it to only 100,000 men. The Treaty of Versailles further forbade Germany from producing or purchasing aircraft, armored vehicles, and submarines. These provisions highlighted the Ententes hope that removing German access to modern technologies of war would force Germany to abandon its militarist past.
At the Treaty of Rapallo in April 1922, Germany and the Soviet Union normalized relations for the first time, the first blow against the postwar order. The following summer, the Reichswehr and Red Army held a series of secret summits during which they crafted the framework for military cooperation.
While Soviet-German military cooperation between 1922 and 1933 is often forgotten, it had a decisive impact on the origins and outbreak of World War II. Germany rebuilt its shattered military at four secret bases hidden in Russia. In exchange, the Reichswehr sent men to teach and train the young Soviet officer corps. However, the most important aspect of Soviet-German cooperation was its technological component. Together, the two states built a network of laboratories, workshops, and testing grounds in which they developed what became the major weapons systems of World War II. Without the technical results of this cooperation, Hitler would have been unable to launch his wars of conquest.
Ian has as well written: The Secret School of War: The Soviet-German Tank Academy at Kama
https://etd.ohiolink.edu/!etd.send_file?accession=osu1338500708&disposition=inline
In the Soviet view WWII started on 22 June 1941 as they were working with Nazi Germany to annex land. https://en.wikipedia.org/wiki/Molotov%E2%80%93Ribbentrop_Pact