Dark Sun: The Making of the Hydrogen Bomb goes into a lot of detail about what was taken and how it was used. What astonished me is that using lend-lease, th

Dark Sun: The Making of the Hydrogen Bomb goes into a lot of detail about what was taken and how it was used. What astonished me is that using lend-lease, the soviets were sending back literal plane loads of documents every week through alaska. The sheer scale of the spying was amazing. The USA mostly let it slide during the war, bigger fish to fry and all that.