From the New York Times article about the decision, "“To hold that the political branches may switch the Constitution on or off at will would lead to a regime in which they, not this court, say ‘what the law is,’ ” Justice Kennedy wrote, citing language in the 1803 ruling in Marbury v. Madison, in which the Supreme Court articulated its power to review acts of Congress."
Of course the Bush Babies are pretty upset. Justice Scalia played a fear-monger card, saying the ruling “will almost certainly cause more Americans to get killed.”
Treating people as human beings has always been risky. But I think America is up to the task.