The Rise and Failure of Militant Socialism
Socialist governments own most or all of the productivity: factories, farms, and sometimes residences. Freedom is limited, because dissent decreases productivity. A few nations have voluntarily gone socialist, but usually socialists seize power violently.
The Communists, Nazis, and Fascists all came into power the same way. The government was in chaos, there were food shortages, and unemployment was high. Democracy was impossible, because the people were too badly divided to form a working majority. A strong man (Lenin, Hitler, Mussolini) then seized power, established order, increased productivity, provided food, and created jobs. So why didn't it work?
Because socialism is based on theft. You have to rob the Jews, the wealthy, foreign investments, and other countries in order to finance socialism. Stalemated against Britain in World War 2, the Nazi socialists invaded the Communist socialists in order to steal the farmlands and other wealth of the Soviet Union. Productivity is stressed under socialism because new wealth is always needed and is not always available through theft. You have to limit freedom, because opposition decreases productivity while raising expenses.
Communist North Korea has nothing available to steal, so it steals its own people. The nation is a giant slave labor camp and is still poverty-stricken. Communist China uses capitalism to improve its cities, but most of the nation still lives in poverty.
And in the Twentieth Century, socialists killed more people than the Atheists (who were included with the Communist socialists). World War 2 was a socialist war that killed 3.5% of the human population (To be fair, Timorlane, "The Sword of Islam," killed 4% of the world population, and he did it with a lot less technology). Add on the other deaths under Communism and Nazism, and socialists have killed more people than all the world's religions combined.