Arthur Koestler opened his polemic against capital punishment in Britain by saying that the island nation was that quaint and antique place where citizens drove on the left hand side of the road, drank warm beer, made a special eccentricity of the love of animals, and had felons “hanged by the neck until they are dead.” Those closing words—from the formula by which a capital sentence was ritually announced by a heavily bewigged judge—conveyed in their satisfyingly terminal tones much of the flavor and relish of the business of judicially inflicted death.

The last hanging in Britain occurred in 1964. Across the channel in France, the peine de mort was done away with by the Mitterrand administration in the early 1980s. So the two great historic homelands of theatrical capital punishment—conservative Britain with its “bloody code” and exemplary gibbetings described by Dickens and Thackeray, and Jacobin France with its humanely utilitarian instrument of swift justice for feudalism promoted by the good Doctor Guillotin—have both dispensed with the ultimate penalty. The reasoning was somewhat different in each case. In Britain there had been considerable queasiness as a consequence of a number of miscarriages of justice that had led to the hanging of the innocent. In France, in the memorable words of Mitterrand’s Minister of Justice, M. Robert Badinter, the scaffold had come to symbolize “a totalitarian concept of the relationship between the citizen and the state.”

Since then no country has been allowed to apply for membership or association with the European Union without, as a precondition, dismantling its apparatus of execution. This has led states like Turkey to forego what was once a sort of national staple. The United Nations condemns capital punishment—especially for those who have not yet reached adulthood—and the Vatican has come close to forbidding if not actually anathematizing the business. This leaves the United States of Am...