Is it true that real communism has never been tried?
The answer to this question entirely depends on one’s idea of “true communism”, as the definition of this has changed so much over the past few decades. According to Karl Marx, communism can only exist when a socialist revolution has successfully led to the state no longer being necessary and it gradually dissolves. It is most certainly true that this classical form of communism has never existed within any country, as for it to exist would mean the country theoretically ceasing to exist.
However, communism and Marxist thought has changed considerably over the past number of decades along with the idea of what defines a true communist state.
Another definition of Marx’s theory would be that a communist state is established when the proletariat overthrows their oppressors and divides the wealth and resources of a nation amongst its people, which has theoretically occurred in a number of regions, particularly Russia, China, Cambodia, and Vietnam to name a few. Even these, however, according to Classical Marxist thought, would not be truly communist nations as the state still existed or exists within these nations, but in a modern and real sense they are (or were) self proclaimed Communist states, which should define them as real communist nations.
As previously mentioned, the answer to the question entirely depends on your own definition of “real” communism, but this statement is in general more of a dialectic exercise than an actual political discussion or analysis.