OK now do Budapest in 1956, Prague 1968, and the defeat of commmunists in basically every free election in Eastern Europe in 1989-91.
Why were there so few migrants from West to East during the Cold War, while, on the other hand, many were willing to risk their lives to go the other direction?
Germany is a near perfect example. The effort required for someone to migrate from West to East was comparatively small. No new language is required, the culture is very similar, and the distance is short. Where were all the true believers in Soviet style Socialism?
Given the similarity of the languages, today we see large migration flows from Romania to Italy. Why didn't we see the reverse during the Cold War?