@Baldimo,
You mean like the five billion the USA promised to pay Vietnam in reparations - RENEGED!
You mean like the plus 300 treaties the USA broke with Native Americans.
You mean like the reparations the USA was ordered to pay to Nicaragua by the ICJ and never did.
You mean like the illegal invasions, the secret overthrow of other countries' governments. That must be what you mean by "responsibility", eh, Baldimo.
How about the promises for the war crimes in Iraq and Afghanistan?