Now that the 2026 U.S.-Iran War appears to be winding down, it is a good time to revisit the role Christian voices played in the debate over the war. Drawing on the just war tradition, many critics of the conflict such as my colleague Brad East raised important questions for how Christians ought to regard the tension between national security and just conduct in conflict. While their points are well taken, these criticisms also seem to fall on deaf ears in Washington. To better equip theologians to address national security audiences the next time war erupts, here are three questions that Christians of all stripes should be prepared to answer to avoid this pitfall.

First, what is war? The answer seems obvious: when bombs fall, guns are fired, and people die. Yet this simplicity is an illusion. Did Trump engage in war by killing Qassem Soleimani in a January 2020 drone strike in Iraq? Or was it war when Iran trained, armed, and financed Iraqi militias tasked with killing American soldiers during the U.S. occupation of Iraq? Rarely do armies take turns shooting at each other in (imaginary) 18^th-century fashion.  

Such questions reflect the ambiguities of warfare in a post-World War II world. In 1954, the Doolittle Report to President Eisenhower stated:

We are facing an implacable enemy whose avowed objective is world domination by whatever means and at whatever cost. There are no rules in such a game. Hitherto acceptable norms of human conduct do not apply…. [we] must learn to subvert, sabotage, and destroy our enemies by more clever, more sophisticated, and more effective methods than those used against us. It may become necessary that the American people be made acquainted with, understand, and support this fundamentally repugnant philosophy.

While its embrace of a “fundamentally repugnant” approach to geopolitics might strike modern readers as repulsive, this report was written at a time when the Soviet Union absolutely sought to subvert American society. Regardless, this text illustrates just how very blurry the lines have become between modern war, intelligence, propaganda, spycraft, and statecraft. For professionals inhabiting this world, to impose a strict set of conditions for “war” but to ignore the rest is a category error. Theologians must first answer, “What is war?” if not a Clausewitzian continuation of politics by other means, a logic that lends itself to total war, not just war.

Second, what role does love play in just war theory? Or, in punchier fashion, what does one do with C.S. Lewis? In his essay, “Why I am not a pacifist,” he admits, “If not the greatest evil, yet war is a great evil.” Yet he then shows the problems associated with rejecting war:

You cannot do simply good to simply Man; you must do this or that good to this or that man. And if you do this good, you can’t at the same time do that; and if you do it to these men, you can’t also do it to those. Hence from the outset the law of beneficence involves not doing some good to some men at some times…. And this in fact most often means helping A at the expense of B, who drowns while you pull A on board. And sooner or later, it involves helping A by actually doing some degree of violence to B. But when B is up to mischief against A, you must either do nothing (which disobeys the intuition) or you must help one against the other. And certainly no one’s conscience tells him to help B, the guilty. It remains, therefore, to help A.

Lewis makes the point that as humans with creaturely limitations, we are unable to always and equally do good to all persons. Thus, in conditions of war, to do good may mean to protect one person through violence directed at another. To illustrate this point, the pilots of the Royal Air Force chose to love their fellow British citizens more than the German pilots they shot down over London in World War II. 

To update this point for the U.S.-Iran conflict, Iran supports groups and governments wreaking all sorts of bloody havoc across the Middle East. To take one example, Iranian financial and military aid sustained the Assad regime in Syria, which horrifically tortured and murdered over half a million of its own citizens before its final collapse. Lewis’s point resonates, even if the history of U.S. intervention in the Middle East is far from a record of altruism. It is necessary to acknowledge the full economy of evils involved in military campaigns such as Operation Epic Fury even if it does not ultimately change the prescription. Aloofness from one’s audience is not a virtue.

Third, at what point does a refusal to go to war constitute a sin, if ever? Aquinas writes that “even as princes lawfully defend their land by the sword against disturbances within, so it belongs to them to defend it by the sword from enemies without.” Romans 13 describes how the magistrate is appointed to punish the evildoer. As the NIV translates, “They are God’s servants, agents of wrath to bring punishment on the wrongdoer.”

Notably, the Apostle Paul does not comment on whether the Treaty of Westphalia limits the application of this principle. Hence, just war theorists should specify under what conditions failure to go to war is an error too, which may entail answering a set of subordinate questions: 

• Does just war theory recognize an obligation to protect, and in what cases? 
• To what extent should the capabilities of a nation inform the scope of wrongdoing against which its leaders ought to “wield the sword”?
• Can national defense in accordance with just war theory encompass the protection of non-territorial dimensions of sovereignty? 
• How should leaders account for asymmetries in national capabilities (cyber, naval, drone, land, air, nuclear) in their calculations of proportionality?

These are difficult questions to answer. One response, found in Magnifica Humanitas, attempts to place war outside the bounds of Christian statecraft altogether. Yet this impulse must be reconciled to Scripture, which commands leaders to serve as agents of God’s authority in the world and asks leaders to “take seriously” their duty to “preserve order, punish wrongdoers, and advance justice.” 

Just war theorists would do well to answer: at what point do leaders bear a duty to make peace, and how? Until then, we might continue to find ourselves tuned out.