What responsibility do we have as a nation to reconcile our past actions that caused unmeasurable suffering for untold millions of people? Have we no courage, no sense of moral obligation to make things right?

The culture of black communities dealing with poverty and crime that you refer to didn't come from nowhere. It was not simply imported from 17th century Africa, in the way that the apple pie was brought over from England. It is a product of a people who were bravely struggling and striving to cope in the worst possible circumstances.

Brutally enslaved for more than 200 years, their literal chains finally removed, they continued to be viciously abused and systematically and savagely oppressed throughout the following century. They weren't event treated as fully human by the federal law until 2 generations ago. Only two generations! Many states had incredibly racist and oppressive laws even more recently than that. The most cursory research reveals an utterly depraved history. One simple and terrible example is redlining, which unfortunately was occurring even after the civil rights act (https://en.wikipedia.org/wiki/Redlining).

We have a duty as a nation to attempt to heal the damage that we have caused. It is impossible to fully mend what we have broken, but we damn well better try.