The reason we should be paying for foster kids' college is because the state is their parent, so it's our responsibility. In a country that wasn't shit, regular people would be jealous of how kids who were wards of the state lived, and how well-raised they were. There's no clearer illustration of our values than the fact that children who, through no fault of their own, have become the responsibility of the state are treated like unwanted trash. The idea that a society like that could figure out how to ethically treat prisoners or immigrants is laughable.
How do you apportion the taxes? Do new immigrants owe the same as people here generations? Do the descendants of Irish immigrants owe the same as descendants of slave owners? What about the black descendants of black slave owners, of whom there were over a thousand?
And how far does this go back? The Comanches were extremely brutal. They killed and enslaved many people from many tribes, especially the Apache. Should they be responsible for reparations to the Apache and other tribes they crushed?