The Supreme Court has ruled that detainees at Guantanamo Bay have the right to appeal their detention in federal court, effectively bringing to an end the nearly seven-year policy of keeping those seized on battlefields or in terror cells in other countries outside the conventional American legal system. The impetus for the Gitmo system, let us not forget, was that Congress declared the nation at war with terrorists, and that it was understood terrorists posed a particular problem because they were operating outside the bounds of the nation-state sytem. They declared their allegiance not to country, but to organization; they lived parasitically inside countries they intended either to attack or to use as a base of operations; and the history of modern terrorism suggested that it was too dangerous to detain them in ordinary prisons, particularly ones outside the U.S., because of the possibility that subsequent terrorist acts would be staged to lead a shell-shocked nation to bargain for their release. By this understanding, the entire world had to be viewed as a battlefield, and a terrorist seized on the battlefield was to be considered not a civil prisoner, but a prisoner of war.

The problem is that this has been, by 20th century standards, an extraordinarily long war — and there was always going to be an issue about how long it would be possible to maintain a detention system of this sort. It has, thankfully, been made more difficult to maintain it because it was so successful — by which I mean, since the Gitmo detentions may well have helped prevent a second major attack on the United States, the sense of imminent danger has lessened and has freed the liberal wing of the Supreme Court, together with Justice Finger-in-the-Air Anthony Kennedy, to elevate the rights of the detained over the safety of the American homeland.