I don't think this is your point, but semantically, doesn't this necessarily assert that either:

1. African Americans were not Americans, or

2. African Americans, the victims of slavery, somehow benefited from it?

I would disagree with both of those assertions.

Further, consider that a vast majority (90%+) did not own slaves. Were non-slave-owners beneficiaries of slavery? What about poor, unskilled whites, who had their own wages effectively suppressed due to the negligible labor costs of slavery - were they really net beneficiaries of slavery? They certainly were not the main victims, but that doesn't automatically make them beneficiaries, either. Slavery was overwhelmingly a horrific practice by wealthy elites for wealthy elites, not by all white people for all white people.