I could argue a great deal with what has been said here about the US system of government. Suffice it to say, I think Sci
is factually wrong on just about every single assertion he/she has made.
However, this is not Miscellaneous or TNZ. This is the TOS forum. And I fear that if I continue to engage in those arguments, I'll help derail what could be an interesting discussion about the government of the Federation
So, veering back to that topic... It seems clear that the Federation is not really analogous to any modern government. It certainly has elements of the United States in it, as well as elements of the United Nations. The key, though, is that they seem to have ironed out whatever flaws exist. And they also have some peculiarities that have never been explained. For example, it seems clear that each member world maintains it's own government. Yet in DS9, we see the President of the Federation -- not the President of Earth -- declare martial law on Earth and put troops in the streets.