For background consistent with the overall theme of this post, I'd strongly recommend Solzhenitsyn's "The Red Wheel" [0], and especially the first volume, "August 1914" (1984 edition).
His intent was not to suggest that the USSR was always backwards, but rather that due to it's history the development was not undertaken until the war. The Tsars didn't do it because they were busy being feudal masters and the communists because they were nation building and hadn't faced the german onslaught yet. Atleast, that is how I understand it. His comment is not an underhanded insult.
> They went from a peasant society immediately to defending against multiple foreign invasions (including the U.S.) to fighting and defeating the fascists, all in three decades. That was achievable only due to their economic and political system.
This is old, debunked propaganda trope recited for a millionth time.
No, USSR never went to industrial giant overnight, for a reason it never been it. USSR relied on single digit of large factories for everything during the war.
Even tiny Eastern European countries USSR invaded were heads above USSR, to the point the first thing USSR did there were stealing all factory equipment, and relocating it to new factories in USSR.
I'm sorry? They went from a peasant society immediately to defending against multiple foreign invasions (including the U.S.) to fighting and defeating the fascists, all in three decades. That was achievable only due to their economic and political system.