Plato’s Utopia was satire. He was too smart to really believe that crap. Over time, the Sophists (akin to modern day liberals) removed the “sarcasm tag” and presented it as his real view.
That’s why it’s so hard to satirize liberals. Just when you think they won’t cross some absurd line, they do(e.g., the current movement to legally redefine marriage).
As with his successors like Voltaire and Marx, Plato was never in a position to put the imaginings of his mind into practice with nasty imperfect humans. That was done later by ego maniacal psychopaths such as Lenin, Stalin, and Hitler with the destruction of millions as the tragic result. Obama and his cohorts imagine themselves in that company and it will take some effort and actions by good men and women to keep them from achieving similar results.