How did France evolve from a constitutional monarchy to robespierre's democratic despotism?

The people first revolted against unfair taxes, and then they decided to establish a constitutional monarchy. The king didn't like that idea and plotted to restore his former power, but he was caught, so his head was chopped off. Then they started a republic. The idea of killing enemies of the Republic seemed like a good idea at first, but it eventually got out of control (Reign of Terror).

In the meantime, anti-Republican forces outside of France decided that letting people think and have self-rule wasn't such a good idea, so other countries with monarchs attacked France. Our friend Napoleon proved to be a good leader, so he and two other guys were chosen to lead the country and put an end to the Reign of Terror.

Napoleon was also adept politically, and he soon nudged his co-leaders out of power, and he became a despot. All this time the other Europeans were attacking France, and he again proved a good general, with lots of victories. He eventually had enough support to crown himself emperor.