Russia was a backward, underdeveloped nation that couldn’t even beat Germany’s B team, and then collapsed into civil war. 25 years later, the USSR beat Germany’s A team and effectively conquered half of Europe, holding it for nearly half a century.

China before the Communists got pillaged by a succession of outside powers, culminating in basically a failed state that barely had a national government. China after the Communists became prosperous and strong, with the world’s second largest economy and no prospect of being invaded.

I’m no fan of Communism and I think a better system of government could have taken these countries farther, but “collapsed their previously great societies” makes no sense.