I’ve probably recommended this to you before, since you seem to be on the same page.
“You can still trust the communists to be communists”
lays out the communist agenda and more importantly, the mindset.
Without a violent revolution, you can’t “accidentally” purge the idealists who would recognize that this isn’t what they meant when they were supporting “the revolution”.
You also need to purge anyone with leadership potential, and in the process, intimidate everyone else into submission.
Purge the population of anyone they perceive as a threat, starting with their own.
Though the content was lost to memory, the cover was still visible to my mind's eye !
Curiosity led me to find an online version of the original that can be read here:
You Can Trust the Communists (to be Communists)