An aspect of political correctness which I have not really considered was pointed out in an e-mail from Henry Harpending: the extent to which PC is motivated by fear and a spirit of appeasement.
Clearly, there is a strong element of fear in the choices of groups upon which political correctness bestows special privileges.
Broadly speaking, the most feared groups are given the highest status by PC.
(One apparent anomaly is women; who, following after slaves and organized labour, were early beneficiaries of the appeasing spirit of PC. An argument could be made that there is indeed a very strong element of fear of women behind political correctness: women being the mutually cooperating arbiters of social status and inclusion, and the sex which (nearly always) controls the sexual arena in which/ for which men are competing. If correct, this would emphasize that for men fear as a motivator is not restricted to fear of violence, although that is often an element, but includes fear of status loss.)
However, feared groups are not treated by political correctness according to the methods of traditional common sense, but instead by appeasement.
Traditionally (historically and still throughout most of the world), feared groups were controlled, subordinated, repressed, excluded and (ultimately) exterminated.
These methods were usually effective - if applied early enough.
However, a deep aspect of political correctness is pacifism: in the sense of a personal reluctance to be involved in physical coercion and even to be complicit in physical coercion.
PC strongly dislikes negative sanctions.
Consequently, lacking access to negative sanctions and especially physical coercion; political correctness gravitates to appeasement of feared groups.
The aim of PC is positive encouragement (of peaceful behaviour), which it does by conferral of privileges, subsidies, bestowal of higher status and so on.
But to do this entails a rationale: the rationale is one of desert: the feared group is seen as deserving of special, positive treatment.
This represents an inversion of common sense government; and culminates in a privileging of the feared group, increased power of the feared group, and ultimately a hand-over of government to the feared group.
Thus appeasement of the feared group becomes transformed into submission to the feared group.
(According to Demonic Males - available on Google Books and a classic account of primate aggression by Robert Wrangham and Dale Peterson - submission is characteristic of some ape females. They explain this in terms of 'warfare' - inter-group aggression. In sum: the difference is that defeated primate males suffer 'murder' and reproductive death; defeated females suffer 'rape' and continue reproduction. When a primate band is defeated, the losing males are exterminated by the winners - 'hence' males must fight and win, or die; but losing females are abducted rather than killed, 'hence' female primates tend to submit to superior force rather than fight. A stark example occurs when gorilla females live in the harem of a dominant male, and a rogue male breaks through the dominant male's defences and kills an infant. The mother of the slain infant will leave the dominant male's harem to join the rogue male who killed her infant. Presumably, because the event establishes which male really is dominant.)
For the PC elite, appeasement at least buys time since the feared groups will be likely to behave well for at least as long as the ruling elite are needed to manage the handover of power.
Furthermore, the PC elite hope (in the teeth of common sense) that the process of appeasement, empowerment and submission will (before the handover is complete) transform the nature of the feared group - such that there will no longer be a need to fear or appease them.
(This analysis leaves open the question of why the PC elite should be reluctant to use traditional common sense methods of dealing with feared groups, what is the cause of this change? This leads back to the deep roots of PC in secular nihilism - and its hopes of an intrinsically altruistic/ unselfish society of optimal gratification and minimum suffering; a society of impartial and abstractly virtuous procedures. In terms of mechanism, the PC elite has its roots in the takeover of society by the intellectual class; who must distinguish themselves from, marginalize and disempower the traditional military rulers, and devalue the analysis and methods of the military class. It is only the military class who are able to apply the approach of control, subordination, repression, exclusion and (ultimately) extermination. For intellectuals to replace, to dispense with, the loathed military class entails intellectuals using non-military methods (even when the alternative methods are ineffective). Alternatively, the process might be conceptualized as consequential to an altered balance of power between the sexes - i.e. progressive feminization: increasing female societal dominance - leading to a reaction to external threat that is ever-less aggressive, ever-more submissive. The two explanations could be combined if the class of intellectual men formed an alliance with women against the class of military men: the intellectual gaining cooperation by appeasement. It all sounds highly Nietzschian!)