marxism

Tbh, there's been a massive re-examination of the USSR since the archives opened in the 80s and 90s. This re-examination has been based on the archival evidence and materialist analysis, and can be seen in works like The Great Urals, Affirmative Action Empire, Arctic Mirrors, On Stalin's Team, etc. This work has not been carried out by Marxists and is often not read by leftists however

Why? For the first, because in general the more marxist you are the less likely you are to 1) decide to go into academia, 2) be accepted into academia, 3) be funded. The people who do this (useful) archival work on events that happened decades to a century ago are going to self select for people more interested in interpreting the world than changing it.

For the second, because 1) the more effective as an org a leftist group is, the less time.they will spend studying hundreds of pages of academic writings, and 2) many marxists either do not know such works exist, or discard them out of hand for not being written by leftists

All this is unfortunate, bc without such detailed examinations of the USSR, China, etc (warts and all) we cannot hope to do better in the future