(I warn you, this is easily the longest entry to date, and is both a bit rambling and less-focused than it would be if it were an answer to an assignment. Read at your own risk, and if you feel like being vitriolic in your comments realize I may just ignore you. :) )
In the process of reading Looking Back at Law's Century, I've just finished Kendall Thomas's article Racial Justice: Moral or Political. It causes me to worry some that the political content of my law degree may be more than I can handle, but then, it's not coursework. Thomas spends most of his article contending that the primary justification for or against a racial interpretation of our Constitution has been moral, but that a more expressly political interpretation is more appropriate.
As an argument goes, it makes sense so long as you accept the fundamental premise: that a moral interpretation of the constitution, whether it is right or not to allow laws which discriminate on the basis of race, have limitations in their normative value. While it's not the whole of his article, I'm most interested in his justification for a political view of racial justice due to the effects of law upon supposed racial 'civic publics.'
According to Thomas (to paraphrase crudely here, in the interest of space), it would be better to consider laws to be racially biased in terms of their political effects, than to concentrate on the moral rights or wrongs of laws which are 'colour-blind' or 'colour conscious.' His major example is the crack/powder cocaine disparity in sentencing in the United States, and he spends several pages contrasting his conception of the policy with another academic, the apparently conservative (or neo-liberal) Randall Kennedy.
Thomas reasons that because many states have laws disenfranchising convicted felons for life, the disparity in sentencing between crack-convicts and powder-convicts hurts 'black civic publics' by reducing both their political efficacy and coherency.  But this presupposes the existence of 'black civic publics' that are distinct from their white counterparts.  In a note, he proceeds at length to argue that this is not the case, and that individual black citizens should have the ability to leave the 'enclaves of resistance' that he claims these policies weaken through disenfranchisement. However, without this notion of a fairly unified black polity, his argument falls to pieces.
The concept that blacks (or other races) share a political culture may describe political reality today, but it is not the necessary political reality, merely what may have occurred because of our current space in history. The idea that any polity to which a standard middle-class black American (the stereotypical 'Huxtable') belongs is weakened by the disenfranchisement of dealer of crack or powdered cocaine presupposes that this person has more political interests in common with the criminal with which he shares a race, rather than his fellow businessmen, professionals, or academics across the racial divide. (The opposite also applies: a white powdered cocaine dealer is assumed to have more in common with a white minister than with his fellow dealer across the colour divide.)
Thomas then goes so far as to say that this common 'political culture' crosses 'racial cultures', and uses as an example New York City:
By way of a concrete example, consider the dynamics of black civic public life in the city in which I live, New York. Black people from the U.S. South, the Caribbean, Central and South America, Europe, and Africa have mobilized around an alternative, activist vision of racial justice in the urban polity. These black counterpublics have addressed issues from police brutality to environmental justice to the politics of race and representation in the city's cultural institutions. An oppositional black public presence in New York City has not required suppression of the myriad cultural (or class) differences among its constituent groups. This is because the political identity of these black urban counterpublics in no way entails the claim of a singular cultural identity. Rather, collective political action by black civic publics in New York City has stemmed from the recognition of a common location in the network of the city's racialized power relations.(102)
But New York City, with a history of racialized politics more extreme than the norm within the United States as a whole, is a bit of an odd example. Besides, constitutional rights span city boundaries (in which races may, by dint of propinquity due to de-facto segregation, be more politically homogenous) to encompass the nation. Besides which, New York City remains one in which politics apportions an appreciable percentage of the spoils of everyday life, and in which de facto segregation not just of races but of ethnic groups ('Little Italy,' etc.) isquite common. The combination of governmentally-apportioned spoils providing stakes and segregated neighborhoods providing opportunity promotes racially-conscious polities, and relatively few forces are working against this concentration. I wonder if Thomas supposes that a national 'black civic public' including individuals from not only cities but suburbs and countryside is sufficiently politically homogenous that a political interpretation of racial justice could be found. Would policies that help the 'black civic public' to which the discriminated-against crack-dealers belong also avail black business leaders and entrepreneurs?
Of course, the political difference I have with Thomas here extends to a conception of the law: whether it is a tool for use in politics, or the rules by which the political game is played. I have always thought of constitutional law as providing a channel within which politics may run, the 'banks of the river' which contain acceptable methods while remaining neutral to their results. My major concern with a political conception of racial justice comes from my economic studies and my thoughts on general systems: what you allow as the boundaries of a system both constrain the possible results and promote the likely ones. Thomas's recommendations of construing racial justice in a political manner do not only ensure that a racial polity may exist, but by providing obvious advantages to members of such a polity against others outside it, ensure that it always shall exist, or at least goes a long way towards promoting its survival against other possible outcomes.
By way of illustration, I'd point to a commonly cited criticism of the Bush administration's preferred alternative to affirmative action. In Texas, a certain percentage of the top graduates from all public high schools are ensured a place in the Texas higher-education system. The New York Times, among others, has pointed out that this system can only be considered effective in helping minority enrollment so long as a de facto segregation of the public schools exists. 
If you hold with the Times editorial page, this is a sign of racism, or at least bull-headed 'colour-blindness' in action. But to a system-thinker, it makes sense as a remedy. If the idea is that minorities are disadvantaged due to unequal access to high-quality public primary and secondary education (due to poverty, lack of English skills, or whatever), then this solution will be racially remedial so long as that segregation exists. If that segregation ends, it will be remedial towards anyone with such limited access, but cease to be racially remedial. As a systems policy, it's near-perfect--limited to those suffering from the identified problem up until the point that the problem no longer exists, while providing a method for eventually phasing out both problem and solution. Of course, it doesn't provide a total remedy (a minority group may be disproportionately affected by other factors than location), but then other policy prescriptions may be put forward for those problems, rather than a 'one-size-fits-all' race remedy.
Similarly, if a minority is disproportionately affected by poverty, than any policy which alleviates the effects of poverty will be disproportionately ameliorative to that minority. It strikes me that by institutionalising 'black' (or other minority) polities, these political thinkers miss a pretty important trick. If one can consider crack/powder distinctions in sentencing to be racist in a 'bad' way, even if the law itself applies equally to any race, then one can consider anti-poverty legislation (for instance, redistributive taxes, union rights, etc.) to be racially-biased in a 'good' way.
This provides a space for minority political leaders to put themselves at the forefront of political movements without having to pigeonhole themselves into being concerned with 'race' issues. The benefit, for instance, of a +20 point advantage to anyone from a disadvantaged family background applying to the University of Michigan might be roughly equivalent for members of racial minorities, or perhaps a +30 point benefit would be needed. In any event, even a larger point increase would be easier to justify both politically and judicially, and by gaining allies outside a self-defined racial 'polity,' it would become much easier to achieve.  The fact that members of a race at the moment have a number of shared political interests by no means implies that they must do so forever, and I would say that the purpose of law is to encourage change such that race is less of a motivating factor, rather than enshrining it as a necessary polity. By removing themselves from polities explicitly bounded by race, politicians would have the ability to advocate change as leaders of true 'rainbow coalitions,' as well as reducing the resistance encountered from those who continue to consider racial justice a moral, as well as political, issue.
 Since this isn't a formal essay, I fully realise that I'm simplifying his argument here. Few of my readers want a twelve page summary, and I don't intend to provide it. If you're interested, I strongly recommend the article, which is thought-provoking.
 Indeed, much of his argument's strength would seem to suppose the existence of 'white civic publics' sharing similar political ambitions, particularly in opposing 'black civic publics.' This unstated homogenity is to me one of the weak points of race-identity politics: the assumption of the monolithic 'Them.' When a poor rural Southern white speaks of the government that is 'giving all the jobs to those minorities' (and who is perhaps a target of old campaign ads by Jesse Helms), he's cursing largely the same power structure as a minority activist protesting crack/powder sentencing laws.
 I say may because I wouldn't concede this point, except in as much that as a voting block blacks as a race are predominantly Democratic. I somehow doubt this is a sufficient condition, though.
 It is important to note here that this is not an argument Thomas makes in his article, but merely one I think is similar to his thesis.
 Consider, for instance, the racial spoils system in the University of California, which at least in the public consciousness for a number of years advantaged blacks as a minority over Asians. A 'race neutral' policy would have allowed leaders to share alliances with anti-poverty groups across the racial divide, instead of the kind of antipathy which eventually led to a 'race-blind' referendum.