Editors’ note: This editorial was originally published at 2 p.m. on April 7, 2025, before the cease-fire was announced. It was updated at 1:30 p.m. on April 8 to reflect that announcement.

On Tuesday, April 7, President Donald Trump came to the brink of committing a war crime. Over the previous two weeks, he had announced, and frequently moved, a deadline for Iran to open the Strait of Hormuz, under a threat to bomb every power plant and bridge in the country. That morning, he posted: “A whole civilization will die tonight, never to ​be brought back ​again.” Within hours, the president of the U.S. Conference of Catholic Bishops responded that such a threat “cannot be morally justified.” Pope Leo XIV called the threat “truly unacceptable” both as a matter of international law and in moral terms.

Both Mr. Trump and the Iranian regime pulled back at the last minute, announcing a two-week cease-fire for further negotiations. We must be grateful for the cease-fire and pray that it leads to a lasting peace. Yet that fortunate outcome cannot excuse the manifest evil of threatening a civilian population. Indeed, to the degree that Mr. Trump’s brinksmanship and apocalyptic rhetoric suggest such threats can be effective negotiating tactics, they move the world closer to the precipice of unrestrained war.

The Catholic just war tradition unconditionally rejects the targeting of civilians in wartime. Not only can noncombatants never be a legitimate military target, but a distinction must be made, the church’s centuries-old teaching insists, between civilian infrastructure that sustains innocent lives and legitimate military targets. So, too, do the Geneva Conventions—to which the United States has been a signatory from the beginning—consider attacks on infrastructure “indispensable to the survival of the civilian population” to be a war crime.

This bears repeating: No matter how much the Iranian regime deserves to fall, no matter how much the world economy is disrupted by its threats to shipping, no matter how much leverage in negotiation the president may gain by these threats, those ends cannot justify these profoundly immoral means. Treating a country’s entire infrastructure as a military target is against all international conventions concerning wartime conduct. 

The United States and Israel’s unjust and unjustified war on Iran has not secured any of the various aims the Trump administration has floated as justification, including the thwarting of Iran’s nuclear ambitions, the elimination of Iran’s ability to wage war, the protection of its citizenry against oppression or any substantial regime change. Even the ceasefire, welcome as it is, promises only to reopen the strait that Iran closed in response to attacks in the first place.

In the past, American political leaders acknowledged the need for moral justification before undertaking military actions in the Middle East and attempted to call upon Christian thinkers and doctrines, including the just war tradition, to supply it, even as the church continued to call for peace. For example, in 2002, Michael Novak visited the Vatican to make the Bush administration’s case for the morality of a second invasion of Iraq; soon after that, George Weigel also made a public case for the war as just, including in the pages of America. (Others, like Drew Christiansen, S.J., argued against it.) 

Not so this time around. While the Vatican has been resolute in its opposition to this war, any jus ad bellum pre-war considerations were largely ignored by the United States. 

While the failure to attempt to justify the war in advance is damning enough, an even more alarming specter has now arisen: the abandonment by the United States of jus in bello—that is, considerations for conduct by combatants within the war itself. 

International law and the just war tradition recognize that limited targeting of civilian infrastructure can sometimes be justified in order to disrupt its possible use by an enemy for military advantage, but Mr. Trump did not bother to make that distinction. Instead, he said these attacks would be carried out as “retribution for our many soldiers, and others, that Iran has butchered and killed” through the regime’s 47-year history.

“If the president is planting a defense for a future war-crimes trial at The Hague, he has not given his prospective legal team much to work with,” Jonathan Chait wrote in The Atlantic on March 31. “As a motive for committing atrocities, ‘retribution’ is more of a confession than an alibi.”

On a practical level, the expansion of the war to include civilian targets could provoke a humanitarian catastrophe for America’s remaining allies in the fight. Iran derives less than 3 percent of its fresh water from desalination plants, but Kuwait, Saudi Arabia and the United Arab Emirates rely almost entirely on such systems. A tit-for-tat military exchange that destroyed that infrastructure would place millions more in immediate peril.

On another ethical level, one jus ad bellum consideration that remains operative in a jus in bello context is also one that should be guiding U.S. military actions going forward: proportionality. This principle states that the destruction and suffering produced by any military strategy should not exceed the anticipated benefits of victory or the amelioration of moral injury being addressed by the conflict. Destroying Iran’s power grid or devastating its oil fields—with the concomitant loss of noncombatant life—for the purposes of regime change is not a proportional response; nor are such actions proportional to the goal of restoring global oil streams.

Unfortunately for all involved in this current war, a proper consideration of proportionality necessarily entails knowing what the end goal is. There is little indication that the Trump administration or U.S. military leaders had an achievable end goal in mind back in March, and Mr. Trump’s prevarications and day-to-day bluster since then on social media and otherwise have provided no assurances in that respect. Instead, we have seen the prospect of abandoning proportionality—in the form of unrestricted warfare—used as a negotiating tactic.

Recent history—including the Vietnam War and both Gulf Wars—has demonstrated that any American plan for overseas intervention that lacks a clear goal as well as ethical guardrails eventually becomes a “forever war,” in which our own soldiers as well as the innocents of the world find their lives destroyed for an undefined or misunderstood cause. 

This current war is also significantly damaging any moral standing the United States may have had regarding its wartime conduct. While it is true that the Iranian regime has itself repeatedly violated contemporary norms around warfare, including the use of proxy militias to target civilian populations, the United States owes itself and its soldiers a much higher moral standard than to be “not as bad as Iran.” The administration’s threats betray the honor and integrity of our military, and risk inflicting real moral injury on our own troops by ordering them to undertake immoral and illegal acts as part of their service to the nation.

The resources of the just war tradition—and of secular counterparts that share its provenance, like the Geneva Conventions—give the world time-tested resources for making whole what is broken. What will it take to convince our own leaders to turn to them for guidance?