It's of little consequence to most of us what historians of the future will say about George W. Bush. More important is whether there will be historians in the future who can work in freedom. That, in turn, depends on the outcome of the war now being waged against the world's free nations.

There are those who will call what I've just written hysterical. They can't imagine the United States being defeated by Islamist regimes and networks. The dismissive question Stalin posed in response to opposition from Pius XII - "How many divisions does the Pope have?" - they ask about al-Qaeda and Iran's ruling mullahs.

The Soviet Union is long gone and the Vatican remains. Moreover, those who believe nations can be destroyed by conventional militaries but not by "asymmetrical warfare" are akin to primitive tribesmen thinking the missionaries crazy to warn about germs: How could such tiny creatures overcome grown men armed with sturdy bows and sharp arrows?

One thing Bush has done right since 2001 is to take the fight to the enemy. The spectacular attacks of 9/11 were planned by militant jihadis operating from a safe haven provided by the Taliban - the Islamist group that ruled Afghanistan in the 1990s. By contrast, terrorists who must hide or stay on the move, who are nervous about communicating by phone or email, who worry constantly that they may be killed or captured are less likely to successfully organize sophisticated operations.

There are those urging Barack Obama to curtail eavesdropping on terrorist suspects abroad, cease clandestine operations against terrorist targets, and grant captured terrorists prisoner-of-war status, and/or the rights enjoyed by defendants in ordinary criminal justice proceedings. To take such advice would invite the next terrorist assault on American soil.

In the current issue of National Review (available on-line to subscribers only, though a related editorial is here), Andrew C. McCarthy - director of the Center for Law and Counterterrorism at the Foundation for Defense of Democracies - writes what may be the definitive rebuttal of the now dominant narrative that the Bush administration violated international law and fundamental morality by not giving captured terrorists "the privileges the Geneva Conventions grant to honorable combatants."

He notes that what we short-handedly call the war on terrorism is complicated by the fact that the existing system of laws and treaties were designed with conventional conflicts in mind. "The animating idea of the Geneva Conventions, adopted in 1949 after the carnage of two world wars, was to civilize warfare," he writes. "Belligerents opted into the system by conduct" - that is, by obeying the laws of armed conflict.

But members of such groups as al-Qaeda (including al-Qaeda in Iraq), Lashkar-e-Taiba, the Taliban, Hezbollah, and Hamas routinely and egregiously violate the laws of war - for example, by targeting civilians, hiding among civilians, not wearing uniforms, and not carrying their weapons openly.

McCarthy, a former U.S. government terrorist prosecutor, also notes that before Bush became president, both the Washington Post and the New York Times editorialized against giving such "unlawful combatants" the status of POWs. Both approved President Ronald Reagan's 1987 decision not to sign "Protocol I," an addendum to Geneva specifically designed to extend to terrorists the Conventions' prohibition against coercive interrogations.

The Geneva Conventions are treaties, and treaties apply only to states that have signed them. You can't conclude they were meant to benefit non-state terrorist organizations unless you also believe there is no meaningful distinction between al-Qaeda and the French Resistance (as some critics of the Bush administration do indeed insist).

McCarthy elaborates: "[T]errorists cannot opt into Geneva. They fall outside because, by definition, they reject its minimum humanitarian requirements. Affording them Geneva's benefits rewards their savagery and undermines the system's civilizing objectives."

It is absurd to suggest that America can prevail in a war against terrorists by prosecuting them after they carry out attacks in which they intend to die. A rational government, conscious of its duty to protect the population, must attempt to prevent and pre-empt terrorists from completing their missions. That requires gathering solid, actionable intelligence.

"The best source of such intelligence is the interrogation of captured terrorists," McCarthy writes. "Applying the steep Geneva interrogation restrictions reserved for honorable combatants would be suicidal: Life-saving intelligence would be lost and no reciprocal benefit achieved for captured Americans, whom terrorists would torture and kill in any event."

It's of little consequence what Obama thinks of Bush. What is important is that not discard policies that are working, and that he grasps McCarthy's central point: Domestic and international law needs to be reshaped into "tools that work against terrorists, rather than for them." The Geneva Conventions are not a suicide pact. If there are free historians in the future, they will understand that.