Update: the 3rd version of this question was deemed on-topic and kindly reopened by 5 members. It has got 4 answers so far and some of these have been excellent in helping me understand the political phenomenon in question.
I have now edited this (closed as too broad) question substantially for the second time to narrow its focus. The 3rd version focuses on factual matters relating to policy, as mentioned in the help centre, and focuses on one nation as recommended in the answers here by senior members. Kindly consider voting to reopen version 3 of this question.
(Old title when voted closed: why has global communism as represented by 'communist states' shrunk to 4 contiguous nations and Cuba?)
I need help to clarify this question which was closed as 'too broad' so that I can edit it into a condition for reopening. You can see what my essential question is -- Why have so many nations abandoned the 'communist state' and why can't communism make a return there: on the other hand, what factors or policy changes have enabled China and the few other communist states to survive the global crisis for communism? It is admittedly broad although I could not assess how broad is too broad here for lack of experience at Politics.SE, but how can I edit it to reopen?
Feedback and guidance especially from the close-voters would be valuable because this is my first question here and I would like you to suggest what modifications will bring it on topic.