All three of those are subsystems of a broader overall system that makes up American society. It's that overall system that perpetuates systemic racism through

All three of those are subsystems of a broader overall system that makes up American society. It's that overall system that perpetuates systemic racism through a combination of factors in the myriad subsystems. Addressing economic inequality along class lines would go a long way, since it's the economic system that has the strongest (or at least most tangible) impact right now. That doesn't do much to address lingering cultural issues, however.