While I don't strictly disagree (I don't see Germany actually conquering the USSR, UK, or US), Germany didn't really capitulate Russia in WWI either; Russia collapsed from its internal problems. That's how you take down earth-spanning hegemons, by wearing out their will to fight. Its not as if Stalin hadn't made a ton of enemies both politically and nationally. Of course, Nazi ideology and tactics rather precluded any effective use of these enemies (the Osttruppen are a far cry from nationalist armies like the WWI Polish or Czechs, and none of the defectors had any political influence in the USSR).
Its less of a case for how they could have won, and more for how they should have tried to win (since it wasn't really evident in 1939 that the USSR or USA were quite so dangerous or resilient).
Naval expansion ultimately would take over a decade to start matching British numbers (ignoring the very high production-capacity of Britain for new ships), and even with all of Russia the Germans really don't have a chance in their lifetime of matching US naval production capacity. Even focusing on submarines alone, subs proved incredibly-vulnerable to dedicated opposition from ASW escorts and aircraft (whether land- or carrier-based). Naval power is more of an industrial game than any other form of warfare.
I don't think WW1 Russia is the same as WW2 Soviet Union. Two different political beasts. Stalin, if he was never asssinated, would have kept sending men and equipment at the Germans to buy his country time to fight back, which he did. Russia would have never been conquered and Hitler HATED the Communist ways of Russia. He would have went after Russia eventually and there wouldn't be any peace. he wanted nothing more than to exterminate them. Which is why I don't think Soviet Union would fall in the conquer sense. Germany's only hope would be to take the resources, especially the oil, solidify his front lines and keep them steady, and focus back on the west while defending the east. Eventually though, Soviet Union would be able to push back as their industry would have been moved further East and their industry would just overwhelm the Germans.
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