Slavery is an unforgivable stain on our souls, something we'll have to live with for eternity. The same goes to the relocation and genocide campaigns against Native Americans. We've never allowed ourselves forgiveness for those sins and we never should.
The brutality in the Philippines sickened Americans to that point that the old colonialism had be traded in for quiet skullduggery. We also learned from the internment camps. When cries came out to round up everyone of middle eastern descent after 9/11 we ignored them and made new mistakes.
Deep down we Americans know that if there is a Hell we probably deserve to go to it, but that doesn't stop us from trying to learn from our mistakes. We are fatally flawed, not essentially evil.
That is the real battle over all of this. It isn't state secrets, but a generational shift. The young live with the cynicism and pain of past mistakes and can't figure out why the old continue down broken paths. Unfortunately, today's young will have to let the generations that follow walk with the knowledge of our mistakes. And what doozies we've handed them: Eternal War, torture and deep resentments and distrust between state & citizen and citizen & state. I wish them luck.