If you are saying that in order for us to have any relationship it is necescary(sp) for it to involve politics. then it is also true that the decision to date within one's race is also a political decision. if so then that decision seems to be a little less strong an argument. first you would have to argue for race ie that we all different and that race is one of the categories, once you have defined race however you so choose physical mental cultural whatever. if you do that, it is not a far run to evaluating those differences based on race. from there easy to move to judging what qualities of said race are better. and then to which race is superior. just using my handy dandy slippery slope.
another thing is that if you do limit who you date aren't you in some way giving power to the "MAN" in that it is all his construct anyway, arent you reacting to the racism in a way that is limiting your own choices, thus limiting your own freedom.