alternatehistory.com

As we learned as the Cold War went on and in its aftermath as things were declassified, the Soviet Union did quite a lot of bluffing and it wasn't as able to compete with the United States as was previously thought. Their number of nuclear bombers was a bluff, their number of atomic warheads was a bluff (hence the "missile gap"), their capabilities in space were a bluff (why they so thoroughly failed in the moon race), their economic strength was a bluff, etc. And the ideas about the USSR were also a mix of Soviet bluff with incorrect US intelligence that overestimated the Soviet Union.

The challenge is to make the Cold War era Soviet Union stronger, with the reference being what the US public thought the Soviet Union was in terms of a superpower that was even ahead of the US in areas. The POD can range anywhere after 1900, but I think it preferable for the scenario of a recognizable Cold War if at most it was circa the era of Stalin and WW2.
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