The official purpose of the Constitutional Convention that met in Philadelphia beginning on May 25, 1787 was to amend the Articles of Confederation. It had, by that time, become clear that the Articles of Confederation were not a good enough constitution for the new nation
The answer here would be Aristarchus. He presented the first known Solar System model that showed the sun as being the center of the universe with the earth revolving it. He was also the first one to show that the Earth rotated on an axis.
The reasons that totalitarian states arose after WWI are many. The economy of many countries was shattered by the costly conflict (especially Germany, being forced to pay reparations), causing socialist and communist ideas to flourish. The scars on society left by the war allowed for embittered populations to be swayed by good orators that could play to the crowd's emotions; Hitler liked to appeal to a desire for revenge in the German people, for instance. Also, as mentioned before, new ideas spread during the war, many involving government, often causing factions to fight over a country, with one finally coming on top, usually led by a single, charismatic individual.