Cf. Frederick Douglass’ What to the Slave is the Fourth of July?. Here’s where it starts to turn from a typical speech into a indictment of hypocrisy:

Fellow-citizens, pardon me, allow me to ask, why am I called upon to speak here to-day? What have I, or those I represent, to do with your national independence? Are the great principles of political freedom and of natural justice, embodied in that Declaration of Independence, extended to us? and am I, therefore, called upon to bring our humble offering to the national altar, and to confess the benefits and express devout gratitude for the blessings resulting from your independence to us?

Well worth the read.