Casting the First Stone

By Michael W. Doyle,
who teaches international affairs, law and political science at Columbia University and is the author of "Ways of War and Peace"
Wednesday, June 14, 2006


A Knife That Cuts Both Ways

By Alan M. Dershowitz

Norton. 348 pp. $24.95

The question of when to go to war lies at the heart of this lively rumination. Lest the stakes be unclear, a photo of Baghdad in flames illustrates the book's cover, and Iraq and Iran each get a separate chapter.

War here is cast as a general choice. Should a responsible government try to deter a potential foe, or should it strike first -- that is, preemptively? Is it safer to wait and threaten punishment than to throw the first punch? Or is it wiser to attack before the risks increase, even though that means taking the chance that danger might not materialize?

Alan Dershowitz, a celebrity scholar of criminal law at Harvard Law School, offers "Preemption" as an attempt to lay out the underlying terms of the debate. His examples of preemptive actions range widely: compulsory inoculations to prevent an epidemic, the profiling of criminal suspects, the "preventive detention" of suspected terrorists, censorship to protect secret technology, assassinations of terrorists or dangerous leaders. At the far end of the spectrum lie preemptive and preventive war -- the former done urgently in the face of an immediate threat, the latter done more reflectively to block (as President Bush called Saddam Hussein) "a grave and gathering danger."

How should we make such judgments? We need jurisprudence, Dershowitz writes -- a set of principles with which to decide the hard decisions we will inevitably face in a post-9/11 world. Dershowitz delivers just that in this vigorous essay sparkling with examples, from the biblical debate between Abraham and God about how many innocents should perish so that Sodom can be punished, through the history of preventive community policing, to the question of quarantines for deadly diseases.

Dershowitz suggests that we rely on a balance of probabilities. He draws on the oft-cited formulation that free speech can be restricted in advance of a "clear and present danger." He suggests that we weigh whether "the seriousness of the contemplated harm, discounted by the unlikelihood that it would occur in the absence of preemption, would be greater than the likelihood of the harms caused by successful preemption, discounted by the likelihood (and costs) of failed (and successful) preemption."

That's a mouthful, but it underscores the need to weigh costs and benefits carefully before taking preemptive action. After all, mistakes are inevitable when balancing probabilities. Like a doctor prescribing a medicine with serious side effects, a responsible policymaker needs to think about correct diagnoses as well as false ones. A doctor with good diagnostic tools and effective medicines can do the job well, but one facing a muddled set of symptoms and armed with less reliable diagnostic tools and cures will sometimes try to treat a disease that's not there.

In criminal law, the adage runs that it's better to have 10 guilty people go free than to have one innocent convicted. But in the preventive detention of terrorist suspects, the reverse may hold: Better that 10 innocents are detained than one jihadist gets through to bring down the World Trade Center, release a deadly virus or explode a nuclear device.

Questions about how to handle Iraq and Iran shape the book. When should states go to war -- rightfully, lawfully -- to protect themselves? Must they wait, as international law holds, for an "armed attack" (as the U.N. Charter requires) or for such an attack (as other key precedents suggest) to be so imminent as to be overwhelming? Or should a potential victim of aggression wait until the U.N. Security Council has authorized a preventive response to a threat -- the notorious "permission slip" that was anathema to both Bush and Sen. John F. Kerry in the last presidential election?

Today, many policymakers rightly worry that waiting for an attack involving weapons of mass destruction means waiting too long. Moreover, unlike national leaders who have something to lose (their regimes, their armies, their economies, even their lives), terrorists seeking to goad a targeted country to overreact may welcome threats of massive retaliation, rather than being cowed by them into more responsible behavior. Nor is the Security Council, which is sometimes wracked by irresponsible vetoes from its five permanent members, always capable of writing a permission slip even when one ought to be given.

One alternative to existing international law is for citizens in democracies to trust their elected leaders to identify threats worth attacking preemptively. But after Iraq, the American public has become less inclined to back such declarations as Bush's famous post-9/11 vow not to "wait to be attacked again," to "take the fight to the enemy" and "to defeat them abroad before they attack us at home."

What, then, does Dershowitz's jurisprudence offer instead? He takes us through some insightful analysis, but, ultimately, he proves disappointingly (though perhaps justifiably) indecisive. He was seriously torn about Iraq but ultimately decided to oppose going to war. On striking Iran to prevent it from acquiring nuclear weapons, he concludes that decision will be guided not by the sort of holistic jurisprudence he has counseled but by more practical considerations: our capacity to find and eliminate Iran's nuclear facilities at acceptable levels of civilian casualties and the prospect of collective action by the international community.

In the end, the right decisions about preemption rest with democratic publics who understand that their actions set precedents that others will follow. Dershowitz asks us the hard questions, and for that, we owe him both thanks and a reading. But one finishes this book wishing he had tried out some more answers.

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