What you're saying may sound all smart and authentic, but it really isn't. If anything, I think its becoming a trending opinion that America is evil and its 'dark' past gives permission for people ignoring the good it has done. And while you explicitly stated that wasn't your intention, I just felt to point this out.
Then there is that we are all created equal. In my opinion, we are not created equal. People have different levels of intellect, different physical attributes, different levels of wealth (that you can be born into). Think about it, would walk up to someone like Bill Gates and say that you are equal to him? I think not. The best we can do to create some level of equality is make laws and rules that can even out the playing field. However, even those laws and rules are broken on a daily basis.
While what Swift says was true (Blacks were considered 3/5s human at the time) its more the fact that I think you're misunderstanding what 'equality' was. You're mixing it up with the popular belief of individualism. What equality was, as stated by the DoI, that all men have certain rights that the government cannot take away, since they are inherent and given from God. (Life, liberty and the pursuit of happiness). Very little to do with the different genetics that allow you to go far in life.
'Evening out the playing field' is opposed since its forcing everybody else to play at the slowest man's pace, thus restricting their freedom, which is counterintuitive. Regardless, you could totally say to Bill Gates that you are equal to him, because you are. Not monetarily, not by intelligence, or even by physique; you're equal to him because you have the inherent right to live and follow your dreams (even if they don't come true.)
Though even I'll admit the federal gov. was totally assholish to the natives, you should also look at it from a less-biased side. The Native Americans didn't want to be Americanized, as most Americans wanted them too, and America was a growing country that had to survive several wars just as it started out. Thanks to the free market and the concept of private ownership, America needed more room to grow because of all the immigrants that, despite of how evil America was, wanted to come here in shiploads. Additionally primitive natives took up a lot of land, because they wanted free-range and buffalo to hunt, etc, and the superstition the settlers had wasn't helping.
As for the freedom of oppurtunity, and how people with different skin-colors and sexual orientations get the short end of the stick is really due to public opinion. Nobody wanted uneducated Blacks to vote due to both racism and the fact that most couldn't read at the time. LGBT caused problems for the many religious citizens of America, but even then they could still vote (in theory) and work hard to get a good job. The government gave them all the rights except marriage, afaik. Public opinion, however, would cause violence against them if they 'deviated' in public. But public opinion is public opinion, nothing was really going to change it except for time (though I think that's part of the idea of legalization gay marriage, to make it simply more accepted.)
Still, gays are allowed to live (even if lynchings are kinda hard to stop), and are allowed to be happy by porking the same gender in private . Just can't be recognized by the government as an actual marriage (for now, at least.)
And then you look at other countries and see how bad they treat gays (Russia, and anywhere in Saudi Arabia), Jews (almost everywhere in Europe), Blacks (Europe as well), etc-- and you realize America isn't that bad afterall.
When this country makes the kids stand and swear, I mean, pledge their allegiance to it, we call that patriotism. When another country does it, we call that brainwashing and indoctrination. When another country/group kill our people, we call that terrorism, but when we do it, it's defending freedom.
Uh... What exactly are you referring to? The first thing that comes to my mind is when I hear a report that Muslim Extremists teach their kids to run into minefields to clear the way, but I think its pretty self-explanatory why I think there's a difference between that and what America does in public school :P. When another country kills our soldiers, they're killing our soldiers. When we send troops to other countries we're primarily defending ourselves from terrorists, lest they take over the government and attack us. (Not that I support giving foreign aid for free, but its waaaaaaay different than how you're wording it, IMO)
That's my take on things, anyway. (Apologies beforehand for grammar errors, its late.)