It's like you've found a typo in a mathematical treatise that doesn't really effect the correctness of the treatise, and gleefully declared the entire thing to be incorrect.
365,000 Americans on the Union side died to end slavery in America, and that conflict was inexorably set in motion by our founding documents that stated that all men are created equal---a revolutionary idea at the time. Today's American government is the same government that eradicated slavery (i.e., the Union).
Regarding Native Americans: The U.S. was the first country in history to declare outright butchery of other ethnic groups barbaric, yet gets the most blame for doing it. The Europeans were still doing it long after the U.S. (e.g. Germany, Russia). You are just trying to find ways to rhetorically "bring down" what was historically the country that actually set the precedent for not brutalizing people. What the U.S. did, and then immediately declared barbaric, the rest of the world had been doing for all of time (and much of it continued, and now continues in China).
edit: Also, the Native Americans didn't have property. They just all used the land around them. Property is something you get when you have organized property rights. If the Native Americans had had that, they would have been set up like a European nation. And if the colonists had slaughtered and taken over something like that (an organized nation), nobody would complain, because that's what European nations had always done, were doing, and continued to do afterwards. It was always survival of the fittest in Europe. It's only when people want to America-bash that Americans are held to a higher standard than everyone else.
Also, American women had property rights; don't know what that's about. I imagine there are nuances we could argue about but let's not.