This dialog is, in at least a limited sense, a reflection of the greater context of the world. Comments about the USA's role in world affairs are all over the map and not even homogenous from USA citizens. Which is to be expected, since we aren't a homogenous people ourselves.
Regarding the USA two-party system, I am against it vehemently. We need at least one more party, perhaps a more centrist-oriented version, or perhaps some variant of Libertarian. The reason is polarization. The country tears itself apart because we have forgotten how to compromise. The political parties push people to vote "red" or "blue" and give them a majority in Congress. Then, when they get it, they run roughshod over the rights of those whose party didn't get the majority.
I'm not going to say that it would solve everything if the USA had three parties of roughly equal size, but having that would FORCE our elected representatives to work towards consensus and compromise rather than working towards gridlock until the next election so they could then force their changes past the opposition. And laying the groundwork for that election by blaming "the other side" for the failure to get anything done. I'm currently ready to vote out the slime-balls - ALL of them - and start with a totally new House and Senate. Except that the candidates we have been getting aren't the type to instill confidence either.
Regarding the USA's role as pushing human rights around the world, I would venture to say that where we do that and in the process push against the established authoritarian government, we become hated because that established government, in a simple attempt to hold on to power, says we should be hated for being busybodies. The people go along with it because in those countries, unbiased news doesn't reach the people. They can't make their own decisions wisely because they don't have everything they need to know. Sadly, the Fox news and CNN news and other organizations have their own agendas and so don't always push out a complete, well-rounded view either. We are victims of that "filtered news" syndrome ourselves.
As to the rationale for the USA pushing human rights, I think that the current trend evolved from the WW2 generation who came home from the European and Pacific theaters of operation with first-hand memories of concentration camps, death camps, and evidence of Man's inhumanity to Man. I know my (now deceased) father-in-law could never forget what he saw during his service. He was part of a unit that liberated a work camp and was forever changed by the horror of it all. He commented on it to me a few times before he passed on.
Many essays and poems were written about what happened in that time, comments about folks looking the other way when the soldiers came for their neighbors, then realizing way too late that folks would look the other way when the soldiers came for them. Not only the Jewish, gay, gypsy, and Seventh-Day Adventists in Europe, but many folks in Nanking Province in China suffered because nobody stood up for their rights. Perhaps we learned that those who ignore history are doomed to repeat it, and we don't want to be an isolationist country because that is how you get crushed by those who surround you with oppression.
I'll get down off the soapbox now.