Wow, there is some real family histrionics going on here. This guy has spent a lifetime acting out against his father, he has been diametrically opposed to just about everything his father has said and done. Now is his time to "get even" with his father and what better way to expose your rage than against the Republican party which was and is the very symbol of the man he could never live up to. Between the Republicans and his needy mother, he didn't stand a chance.
Bush is a convenient target for him at the moment. If it wasn't Bush or the Republicans it would be another group that advocated the fundamentals that were at the heart of Reagan's convictions.
His issue is with his father, I agree, but it is even deeper. His struggle seems to be against the God he claims to have no faith in.
His words intially angered me at the funeral. Now, I do not like the character of the man but find myself caring about him in spite of his actions. He is Reagan's son, after all. It can only be imagined how grieved the father that was the former President must have been over the spiritual condition of his son. I find myself praying for him for this reason.