I agree with the second part of your post, Wry.

Plato outlined what you said in the Republic. Nations with democratic societies or representative governments devolve, over time, into various despotic forms of tyranny. Democratic or representative style govs. always devolve into plutocracy, oligarchy and finally in tyranny. These transformations take years, sometimes centuries but our society is not immune from this phenonmenon.

What is so poignant about Plato's point here, is that he was writing this circa 500 bce. His predictions have played out in all societies all over the world since he wrote about this. For that, Plato was a visionary, a genius!