In the preface to the second edition of his now classic Just and Unjust Wars, philosopher Michael Walzer wrote of a “significant revival of just-war theory” that was sparked by the U.S. experience in Vietnam. Indeed, just war language has surfaced not only in church discussions but also in public policy debates—about nuclear deterrence during the 1980s, the invasion of Panama in 1989, the first Iraq war in 1991, the humanitarian intervention in Kosovo in 1999, and the wars in Afghanistan and Iraq following the terrorist attacks on September 11, 2001.

Of course, it is possible for the just war tradition to be invoked concurrently by those who disagree on whether a particular war is justified. For example, Catholics George Weigel and Michael Novak employed just war criteria to argue that the U.S. war initiated in Iraq in 2003 was just, while many other Catholic ethicists and church leaders, including Cardinal Joseph Ratzinger (now Pope Benedict XVI) and Pope John Paul II, were led by just war reasoning to express doubts about the war.

This disagreement goes deeper than differences over how to apply principles to concrete cases. Indeed, as David P. Gushee deftly pointed out in these pages (“Just war divide,” August 14, 2002), just war judgments are colored by different underlying assumptions. There are at least two rival versions of just war theory. My teacher John Howard Yoder used to refer to one as having “teeth” and the other as “without teeth.”

Just war theory “without teeth,” which Gushee refers to as the “more hawkish” version, is inclined to be more permissive when it comes to labeling a war as just. One of the characteristics of this school is that it begins with a presumption against injustice—that is, a presumption that arms can be taken up to address injustice. But as Yoder noted, just war theorists of this school tend to consider any given war conducted or tactic used by the U.S. as just. He worried that by focusing on the jus ad bellum criterion of “just cause,” this version of the theory may encourage the setting aside of the other criteria of just war on grounds of “necessity.” As it turns out, all (as far as I know) those who subscribe to this school of just war indeed claimed that the war against Iraq was just.

On the other hand, the proponents of the “with teeth” version, such as the U.S. Catholic bishops and the United Methodist bishops in their respective pastoral letters on war and peace from the 1980s, hold that just war starts with a presumption against war. According to this—as Gushee labels it—“more dovish” version, the burden of proof rests upon those who are considering resorting to lethal force. All the criteria are thus applied more stringently. Most, though not all, of those who adhere to this version of just war regarded the war against Iraq as unjust.

The characteristics that Gushee associates with the hawkish version of just war are evident in Between Pacifism and Jihad, by J. Daryl Charles, who is associate professor of religion and ethics (and a colleague of Gushee) at Union University in Jackson, Tennessee. Written with an evangelical Protestant audience rather than other scholars in mind, Charles hopes to show that the current terrorist threat “underscores the abiding relevance of the just-war tradition.”

Although he rightly maintains that the just war tradition steers a course between the two poles of pacifism and militarism (he includes jihad and crusade as religious versions of the latter), Charles directs most of his criticisms at religious leaders and academics (a number of times he rails against academics without naming or footnoting anyone) who have assumed a pacifist stance and thus have made “many depressingly irresponsible comments” about how the U.S. ought to handle threats from terrorists and rogue nations. Despite a few warnings against “national idolatry” and a few calls for humility and recognizing our “ultimate allegiance—to the Creator, the Ruler of the nations,” Charles spends little time criticizing militarism.

Through a survey of biblical passages and the thought of a number of theologians, Charles argues that just war, “properly understood, begins with the presumption to restrain evil and protect the innocent, not to forbid coercive force.” As such, just war is about “responsible statecraft” and “responsible citizenship” rather than faithful discipleship. Pacifism, in contrast, is “irresponsible.”

Charles assumes that pacifism involves a “refusal to resist evil directly through action,” and he rehearses the standard (and inaccurate) criticism that pacifists such as Yoder and Stanley Hauerwas call for the church “to leave the world and to form communities that by their very existence are a light to the world.”

Nowhere does he seriously address pacifism as active nonviolent resistance, except when he asserts a couple of times that pacifism’s effectiveness in countering totalitarianism and other serious threats “has not yet been sufficiently demonstrated.” Perhaps he should consider the nonviolent overthrow in 1986 of the brutal dictator Ferdinand Marcos by millions of unarmed Filipinos, or what Pope John Paul II wrote in Centesimus Annus about the collapse of the Soviet bloc due to “the nonviolent commitment of people who . . . learn to fight for justice without violence, renouncing class struggle in their internal dispute and war in international ones.”

For Charles, war is a “permanent fixture” in the present fallen age, and God’s peace represents “ultimate, not penultimate, reality.” Thus his version of just war theory differs from that of those who, like the U.S. Catholic bishops, acknowledge the threat of war due to the continuing presence of sin in the world, but who also hold that because of Christ’s life, death and resurrection God’s peace is possible in this world to some extent and that war is not inevitable. It is within this latter framework that the Catholic Church calls upon its members, whether pacifists or just warriors, to tackle injustice and to defend the innocent. Charles wrongly describes the U.S. Catholic bishops’ position as “categorically” ruling out the possibility of war or coercive force. As Kenneth Himes, O.F.M., helpfully puts it, “The case for war should be difficult to make. Not impossible, but difficult.”

A more dovish understanding of just war is offered by Joseph J. Fahey, who provides a balanced and well-organized survey of the various positions. Fahey, who has many years of experience as a professor of religious and peace studies at Manhattan College and who was a cofounder and general secretary of Pax Christi, USA, brings to life the historical material he covers by writing to a fictional student, “Nicole,” and inviting readers to write letters to her as an exercise in expressing their views on questions included at the end of each chapter.

Fahey sets the tone for the book by reflecting on the nature of conscience and on how various shapers of conscience—including culture, religion and other variables—contribute to our ethical perspectives. In his view, we have a duty as Christians and as citizens to form our conscience about war.

Fahey argues that just war begins with a moral presumption against war, so that there is “a very heavy moral burden placed on civilian leaders and military officers who would lead young men and women into war and who would ask a nation’s people to support a war.” Like Charles, he surveys scriptural passages and the contributions of major Christian thinkers such as Augustine and Aquinas, but unlike Charles he takes into account the church’s liturgical and disciplinary practices, such as the assigning of penance for killing, even in a just war (a practice that took place from the sixth to the 12th centuries).

Although Fahey tries to present each approach to war fairly, his preference for pacifism as nonviolent resistance and for a more cosmopolitan world order that will outlaw war shows through. On the latter, he notes that there will need to be a global police force for enforcing international law, and in his chapter on pacifism he observes that many pacifists support police forces and the coercive power of domestic and international law. However, it remains unclear whether an international police force would have to be nonviolent or would be allowed to use force, including possibly lethal force, if a rogue nation or terrorist group breaks the law that outlaws war.

Even in domestic situations, whether in the case of the relatively unarmed bobbies in the United Kingdom or in community policing programs that seek to prevent crime nonviolently at its roots, access to lethal arms remains a possibility. And any use of force by the police, whether local or global, requires criteria governing when and how such force can be employed justly. As the Rodney King beating by some Los Angeles police officers in 1991 demonstrated, not all policing is just policing.

There are such things as police brutality and excessive force, and these certainly cannot be what a pacifist or a proponent of world order has in mind when suggesting the extension of a police approach from the domestic to the international sphere. Rules are necessary, and, as Yoder noted, the criteria governing police use of force resemble those of the just war tradition, even though there are significant differences between warfare and policing.

This is one area that Charles gets partially right. While Fahey and Charles agree that the just war criterion of “just cause” allows for preemptive force against a grave and imminent threat, Charles makes his case by relying on an analogy with policing. He writes, “Suppose a stalker-murderer were on the prowl in your neighborhood. . . . Should the police wait until he rapes, maims and kills before they intervene?” However, Charles is only partly correct because he focuses on just cause without proceeding to consider how other criteria also come into play in such a scenario. Moreover, his invoking of policing may work against his version of just war, given that much of the literature on police ethics, such as John Kleinig’s The Ethics of Policing, holds that policing begins with a presumption against violence.

Most Americans, including Christian ones, approach every call to arms issued by the government with a strong presumption in favor of war. Given this state of affairs, we could use more books like Fahey’s.