Earlier quoted context omitted.
It was literally founded on those things, in the sense that the original inhabitants were about 50% indentured and they built the damned place. Saying that the US wasn't founded on these realities is like saying the AU wasn't founded as a prison colony.
So, by your logic, anything happening during a country's founding we deem today as bad means that country was founded on those bad things. Then every single country on Earth in all of human history was founded on bad things. That's silly logic.
If you can't or won't argue the points I'm actually making, don't try to inject your own version of what you think I might be saying.