I recommend Sean McMeekin's "Stalin's War". It was printed in 2021. Bottom line, the Red Army was incapable of winning without the massive support of the US and UK in the form of Lend Lease, and the military campaigns in North Africa, Italy, and in NE Europe. The war in the Atlantic was also a huge factor. Stalin would have collapsed within the first year of the invasion without this help.
I recommend Sean McMeekin's "Stalin's War". It was printed in 2021. Bottom line, the Red Army was incapable of winning without the massive support of the US and UK in the form of Lend Lease, and the military campaigns in North Africa, Italy, and in NE Europe. The war in the Atlantic was also a huge factor. Stalin would have collapsed within the first year of the invasion without this help.