The Roman Republic...The Roman Republic was governed by a largely unwritten complex constitution, which centered on the principles of a separation of powers and comprised a host of checks and balances.
I find the circumstances that evolved within those societies to reveal a paradigm shift in thinking, attitude, and expectations akin to 'I deserve the good life'. Add to that, moral decay, poor leadership, over extension of their governments and military (performance versus funding / income), etc., etc., etc., to be reticent in within the halls of US government today, especially, our elected officials.
Both empires crumpled when conquered subjects tired of over taxation accompanied with apathetic elitist attitudes of their rulers, not withholding the citizens acceptance from their self imposed stagnation and commonality of their own way of life documented from the demands of barbaric entertainment from the masses.
Too much today with what's wrong with America parallels the fall of Rome. Students are no longer required to study the histories of these once great ancient societies and the writings of those great philosophers of those eras.
Therefore, we can not expect them to even begin to grasp the potential, the opportunities, and responsibilities that have been laid into their hands from the blood, sweat, tears and wisdom of our forefathers. This is what is truly sad now.