I read a biography about the great Roman lawyer/orator Cicero. It’s been a while but if I recall it discussed how their Republic fell. Many factors were involved but when the sides stopped using the vote and started attacking each other to see who had power it died quickly.
After personal attacks and so forth finally one side used the military which was followed by the other side which led to full out civil war. After that the Emperor system was instituted.
All empire collapses where closely connected to the government printing money and devaluing the currency. The US central bank has been printing more money I think every decade and will not stop until it ends the country.