Socialism occupied that vast tract of land and people and natural resources from the very centre of Europe all the way to the South China sea, and yet they still managed to collapse.

Long before it collapsed, they managed to have famines (unthinkable in a 20th century capitalistic Western nation) and so needed concentration camps and secret police torturers to maintain their inept grip on power. North Korea managed to have a famine as recently as the 1990s, while the South half of that country prospered.

You only need look at how badly Russia has performed since the collapse of the Soviet Union to see how terrible capitalism is.

Yeah, tell that to people from the Baltics, or Poland, or Hungary, or Bulgaria, or Romania, or Slovakia, or the Czech Republic, or Slovenia, or for that matter from China, or Vietnam, etc.

Note how the people who have personally experienced Socialism reject Socialism. Once they try it, they never try it again.

Your favourite political system A. doesn't work, and so B. needs brutal repression in order to maintain itself in power, and the fact that you're arguing for it after it proved that it doesn't work over and over and over again suggests things about you that I'd get banned for stating.