Freedom is not merely the opportunity to do as one pleases; neither is it merely the opportunity to choose between set alternatives. Freedom is, first of all, the chance to formulate the available choices, to argue over them - and then, the opportunity to choose.
If you believe that every life has equal value, it's revolting to learn that some lives are seen as worth saving and others are not. We said to ourselves: "This can't be true. But if it is true, it deserves to be the priority of our giving."