Changes

I don't think Niebuhr and Hartshorne are really notable figures in American philosophy, and Mills was a sociologist, not a philosopher.  If you want American philosophers of religion in there, the obvious choices should be Plantinga and Hick.  But - on that note - "American philosophy" is really limited to Pragmatism (or Peirce's 'pragmaticism', since he hated James), in the 20th century most famously championed by Rorty.  Other than that, the meaningful distinction is (as I noted in the top section) the divide between Analytic and "Continental" philosophy.  Rawls, for example, is squarely in the Analytic camp, not the American (read: Pragmatic) camp.

I don't think Niebuhr and Hartshorne are really notable figures in American philosophy, and Mills was a sociologist, not a philosopher.  If you want American philosophers of religion in there, the obvious choices should be Plantinga and Hick.  But - on that note - "American philosophy" is really limited to Pragmatism (or Peirce's 'pragmaticism', since he hated James), in the 20th century most famously championed by Rorty.  Other than that, the meaningful distinction is (as I noted in the top section) the divide between Analytic and "Continental" philosophy.  Rawls, for example, is squarely in the Analytic camp, not the American (read: Pragmatic) camp.