"power" to carry out successfully actions based on them would issue in "Justice."
Somebody: Right. In other words, Carrol's lack of ethic is equivalent of the immorality of Thrasymachus in The Republic: might makes right.
But notice how he shifts to saying that justice becomes genocide in some circumstances, when one group is no longer dependent on the other. But why shouldn't we term genocide the form justice takes in this instance, by his reasoning?
Ironically, Marxists are really going to have to move beyond this "everything through the class struggle" lens if they're actually going to have much success in winning the class struggle. Short term expediency has a way of discrediting one's goals, however noble.