A better question is, what makes people think Bush CAN do anything? He can't use executive order to overturn a judgement, that's against the rules too, separation of powers. Only a higher court can do that. What he CAN do is order a constitutional amendment strengthening the intended wording, but still that will not overturn the judgement made, and the people who lost out because of it.
Bush can use the issue politically in the battle over judges. that's what he should be doing, but they are so feaful of criticizing any court decision.