Some reflections on the two. Money quote:
Niebuhr's insistence that the powerful would only relinquish their privileges when confronted with organized force--not moral appeals or progressive education--remains indispensable to any realistic effort to win dignity and a decent life for ordinary people. And his argument that "non-violent coercion and resistance" was the most humane form of mass protest still inspires with its hope for future reconciliation and forgiveness between adversaries. Non-violent protest, a strategy Niebuhr explicitly recommended to African Americans, "binds human beings together by reminding them of the common roots and similar character of both their vices and their virtues."