The difference between colour blindness (equality before the law) and your examples is that your examples are not mutually exclusive. You can save the rainforest and the arctic at the same time. You cannot give the final scholarship place to both the Cambodian and the African American. Whatever you give to one is taken from the other, and it cannot be any other way.
Your argument seems to hinge on the idea that you should not take action to help one disadvantaged group if that action excludes a different disadvantaged group. Is that a fair summary of your point?
Do you think this applies to all disadvantaged groups, or just when discussing issues of race?
