Like I've said previously, the 'socialist' nations in the world today (China, North Korea) are not socialist in nature. They are state capitalist and totalitarian states, respectively. 
As a socialist I decry the Marxist-Leninist variety of socialism for being overly authoritarian; however, one cannot deny the success of the socialist system in Cuba. 
Cuba has a literacy rate of 99.8%, (up from the low 70s before the socialist revolution) according to the World Bank, compared to just around 80% for the US. This is owing to the fact that education is free at all levels and highly accessible. Cuba was the first nation to sign, and second to ratify, the Convention on the Elimination of All Forms of Discrimination Against Women, a UN treaty that has since been ratified by 189 countries. 
The growing wealth inequality in Cuba, like many (but not all) of their economic weaknesses, is caused by the brutal US commercial and trade embargo of Cuba that began in 1960. This embargo bans trade between Cuba and the USA, which has had tragic effects like shortage of goods such as medicines, medical supplies, and the weakening of public services and infrastructure. Not only has this embargo impacted direct trade between the US and Cuba, it has also affected third countries' ability to trade with Cuba, leading to even worse economic woes. 
The UN has repeatedly and consistently condemned the embargo since its application, but the US won't lift the embargo, because they fear what would happen if a socialist nation would be able to fully operate properly. The years of anti-socialist fear-mongering and 'socialism never works' propaganda would be disproven in a matter of years. 
It's no wonder we say 'socialism never works', because whenever the people try to implement it, they are locked into a permanent economic stranglehold by powerful, wealthy nations. 
However, I won't die on the hill of China, and certainly not North Korea, so don't pretend I will.