Cockburn's operating principle is "the worse, the better." It is not usually explicit in his writing. His view is whatever disrupts the system without casting specific discredit on the left increases the possibility of revolution. This view is antithetical to any sort of social-democratic, incremental, or reformist view, as well as to some more sophisticated, more radical views of how a revolution might take place.
Putting the onus of the father's record on the son is silly, particularly in terms of the Stalinist rap. The son inclines towards Trotskyism, if I read him correctly.