In part I, discussed how an individual can break down moral boundaries by casting doubt on the underlying presuppositions. Now for the manipulation. Not only are morals susceptible from within a person, they are suspectible to attack from outside as well.
Using the same formula as before:
A is true, and B is true, so action C is a moral behavior.
Not every person has the same mental capacity or the same zeal for rigorous intellectual pursuit of consistent logical behavior. Because of this, some are better at changing minds and others are more likely to have their minds changed. Those who are better I will call "authorities" and those who have their minds changed I will call "followers".
The problem is that authorities are not altruistic, and in regards to spreading the one objectively true morality (A and B) they may balk because it doesn't serve their interests or preferences. If it is in the interest of authority figure X that follower Y not practice behavior C, X will use its authority power to persuade Y not to practice behavior C. Moral laws break down because they do not serve the interest of the authorities. Follower Y is not aware that they are serving the interest of authority figure X, only that the authority figures makes sense.
Jesus saves his anger for authority figures alone. The Pharisees and the "Teachers of the Law" lord their expertise over their people and coerce them to beleive and practice things that serve to maintain the status, power, and wealth of the authority figures. Jesus eviscerates them on several occassions. As for today we have "name it and claim it" preachers, media propagandists, and Global Warming theorists :)
Other forms of blatant manipulation come to mind, but we all, in subtle ways practice this. Parenting is the profession of this practice. How do I get my son not to hit the other son? Moral imperitive. How do I keep them out of the street? A car WILL hit you (with high probability). It's exaggeration, manipulation, and a whole menagerie of half-truths and cliches. If anyone has any better ideas please let me know.
Morality breaks down because talents are dispersed. If we assume that the strong will accumulate more resources by the sweat of their brow, and that the smart and industrious will join them by focusing their faculties, then we must accept that the crafty and surreptitious will do it by changing our morals through manipulation.