US independence was a huge event! This definitely laid the foundations of this great nation.
I find particularly interesting the fact that the thirteen former colonies kept their autonomy. In my opinion, Americans wanted to be the master of their own destiny: nobody rules them but themselves.

Regarding the elections, I would say that the system of national Presidential elections is a little bit difficult to understand. Citizens who want to vote must register as voter (it is not obligatory to vote in US). In addition, the “Electoral College” reports the “electoral votes” which are equal to the number of Senator and Representatives each state has in Congress. Despite its complexity, it seems to be the best system for Americans.
Finally, while in many countries there are plenty of political parties, in America there are just two (in fact, there are more, but they do not influence too much): the Republicans and the Democrats. The traditional European terms of “right” and “left” may fit these two parties, but it actually does not. For example, a Democrat could be “liberal” as well as “conservative”. It is necessary to study these political parties without any “denomination”.