Catholic Just War Doctrine in a Time of War

I am not a theologian, but I relied on the Catholic just war tradition during a time of war, when the decisions before me carried consequences measured in human lives. That tradition, refined over nearly two thousand years, exists precisely for moments like that. Today, the Church articulates that tradition through a clear moral framework—what we call just war doctrine. 

I want to make a case—to Catholics and non-Catholics alike—that this tradition matters now. Pope Leo XIV has spoken powerfully about peace. That emphasis may reflect a pastoral corrective in a violent moment, but he has not engaged with the doctrine the Church itself provides.

The Library No One Talks About

For much of Western history, the Catholic Church preserved one of the world’s great intellectual traditions, producing thinkers such as Augustine and Thomas Aquinas. These were rigorous minds who wrestled with the hardest moral questions and left a body of reasoning that remains coherent and serious to this day.

You do not have to be Catholic or accept every teaching of the Church to recognize its intellectual seriousness. But on moral questions—war, life, justice—you will be far better informed if you have considered what it says in its official doctrine on these issues. That is not a claim about faith. It is a claim about intellectual seriousness.

The Catechism of the Catholic Church is one such document. What it says about war is worth knowing, especially now.

A Framework Built for Hard Moments

The Church has never been pacifist. It holds a deep and genuine presumption against war, but it has never taught that force is always wrong. Instead, it has done something harder: it has tried to define when force can be morally justified and under what conditions.

This is what we call the just war doctrine, and its roots run from St. Augustine in the fifth century through St. Thomas Aquinas in the thirteenth century to the modern Catechism. It has shaped international law, the Geneva Conventions, and the moral reasoning of military officers, heads of state, and ordinary soldiers across centuries and denominations.

The Catechism of the Catholic Church (CCC 2307–2310) sets out four conditions that must be met for the use of military force to be morally legitimate. The damage inflicted by the aggressor must be lasting, grave, and certain. All other means of resolution must have been shown to be impractical or ineffective — force must be a last resort. There must be serious prospects of success. And the use of arms must not produce evils graver than the evil being eliminated — the principle of proportionality.

These are not vague sentiments. They are criteria — specific, demanding, and intended for application to real circumstances. They do not guarantee easy answers. Reasonable people of goodwill, applying the same framework to the same facts, can reach different conclusions. The Catechism itself acknowledges this, stating that the evaluation of these conditions "belongs to the prudential judgment of those who have responsibility for the common good."

That is the point. The Church gives us the moral architecture and trusts us — citizens, leaders, and soldiers — to apply it honestly to the facts before us.

What the Pope Has Said — and What He Has Not

Pope Leo XIV has spoken forcefully against the current U.S.-Israeli military campaign against Iran. He has declared that "God does not bless any conflict," that "God does not listen to the prayers of those who wage war," and that disciples of Christ "never stand on the side of those who once wielded the sword and today drop bombs." He has called for an immediate ceasefire and a return to dialogue.

These statements carry the moral weight of his office, and the pastoral concern behind them is genuine. No serious person dismisses the suffering of civilians in any conflict or the Church's ancient call to be peacemakers. That call is real and non-negotiable.

But something important is missing.

The Catechism does not say what Leo's statements imply. It has never said that force is always wrong. The Church's own teaching leaves open the moral possibility of legitimate defense. And when a pope speaks as though that possibility does not exist — without walking through the criteria or explaining why these conditions are not met — he leaves his flock without the very tools the Church exists to provide.

Consider Pope Leo's own family history. His father, Louis Marius Prevost, served as executive officer of a Navy tank landing ship during World War II. He participated in the D-Day landings at Normandy on June 6, 1944, delivering soldiers to those beaches. He later served in Operation Dragoon in southern France. After the war, Louis Prevost returned home and became a catechist — a teacher of Christian doctrine to the next generation. He had looked directly at the moral weight of war, borne it with honor, and then spent the rest of his life handing on the faith.

That generation's war — waged to defeat Nazi tyranny at enormous cost — is one of the clearest cases in which the criteria appear to have been met. Millions of faithful Catholics in uniform, likely including the Pope’s father, prayed for protection, for their comrades, and for the innocent. The Church has always honored their sacrifice. Declaring categorically that God does not hear the prayers of those who wage war risks contradicting the very tradition the Pope is called to teach — and the witness of his own father's life.

Were my own prayers in 1991, when my work contributed to targeting decisions in the Persian Gulf War, offered in vain? The Church’s answer has always been no. Pope Leo’s statements leave that answer dangerously unclear.

What We Actually Need

We live in a moment of profound moral confusion about war and peace. Social media has reduced complex questions to slogans, and political identity has replaced moral reasoning. Those who oppose the current administration will reflexively oppose the war; those who support it will reflexively defend it. Neither posture requires thought or yields wisdom.

This is precisely the moment when the Church's tradition of rigorous moral reasoning could cut through the noise. It is neither a conservative nor a liberal framework, nor is it American or European. It is a structured method of moral assessment that asks the same hard questions regardless of who is fighting or who holds political power. It demands honesty about facts, humility about uncertainty, and seriousness about consequences.

Applied faithfully, it might lead a thoughtful Catholic to conclude that a particular conflict is justified. Applied with equal faithfulness, it might lead another to conclude that it is not. That disagreement is not a failure of the doctrine — it is the doctrine working as intended, replacing tribal reflex with an examined conscience.

What it cannot do is work if it is not taught.

A Respectful Plea

Pope Leo, your calls for peace are heard. The Church's presumption against war is real and right. Every civilian death is a tragedy. Every resort to arms is a failure.

But the Catechism does not forbid the virtuous defense of the innocent when the conditions of just war are genuinely met. Your own father understood this. He delivered men to the beaches of Normandy, came home, and spent his remaining years teaching the faith to children. He did not see a contradiction between those two things — and neither has the Church, in two thousand years of reflection.

Guide us through how this teaching applies in this case. Tell us why, in your judgment, the threat does not meet the standard of lasting, grave, and certain. Tell us why diplomacy has not been exhausted, or why the evils of action outweigh those of inaction. You may be right. The doctrine allows for that conclusion. But the doctrine requires an argument, not just an assertion.

The Church has given the world an extraordinary gift in just war teaching — a framework serious enough to guide conscience through the hardest human decisions. Use it. Teach it. Trust your flock to think.

That is what the greatest library in the world was built for.

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The Strait of Hormuz: Secure the Present, Build a Different Future

In the late 1980s, I worked at the Office of Naval Intelligence, supporting U.S. naval operations in the Persian Gulf. One of those operations was Earnest Will, the largest convoy escort mission since World War II. American warships protected reflagged Kuwaiti tankers from Iranian mines and small-boat attacks. Despite those threats, the operation succeeded. The Strait remained open, and Iran ultimately backed down.

That success, however, masked a larger failure. We solved the immediate problem but left the underlying one intact. Iran retained the ability to threaten the strait, and the world remained dependent on it. Four decades later, we are paying the price.

Today, the Strait of Hormuz is effectively closed again. Commercial shipping has fallen by more than 90 percent, and millions of barrels of oil per day have been removed from the market. Prices have surged past $100 a barrel, and economies that depend heavily on Gulf energy, particularly in Asia, are scrambling to adjust. This was not an unforeseen development; it was the predictable result of a vulnerability that was never addressed.

Birthright Citizenship: A Personal Take on the Supreme Court Arguments

This week, I listened to the Supreme Court’s oral arguments in Donald J. Trump, President of the United States, et al. v. Barbara, et al.—a case that could redefine birthright citizenship in America. Both sides presented serious legal interpretations, and anyone claiming certainty about the outcome is probably allowing politics to influence their thinking. We should expect a ruling by the end of the Court’s term in June.

My interest in this case extends beyond academic curiosity. I minored in law during college and seriously considered law school, but I ultimately pursued a career as a Naval Intelligence officer. While serving in Washington, D.C., I lived just a few blocks behind the Supreme Court building and the Capitol and spent years witnessing how law and policy function in real-world situations—often in more complex ways than they appear from an outsider's perspective. This case is just as complex.

Some History Worth Knowing

The 13th, 14th, and 15th Amendments, ratified between 1865 and 1870, aimed to rebuild the nation after the Civil War and ensure equal rights for formerly enslaved people. The 14th Amendment, in particular, granted citizenship to “all persons born or naturalized in the United States, and subject to the jurisdiction thereof,” while also securing due process and equal protection.

That language was clear in its immediate purpose but left room for interpretation—especially the phrase “subject to the jurisdiction thereof.” That ambiguity is precisely what the Court is now being asked to resolve.

Book Announcement: Brotherhood and Borders

 After more than a decade of writing about immigration and political division, my new book is now available on Amazon:

Brotherhood and Borders: Immigration, Compassion, and the Rule of Law in America

Immigration is not simply a border issue. It is a moral issue, a structural issue, and ultimately a credibility issue.

This book examines:

• Why reform efforts repeatedly fail

• How political incentives distort outcomes

• Why enforcement moved from controlled settings into public confrontation

• And what success would actually look like

It is written for readers who want structure instead of slogans.

Available now in hardcover and Kindle at this link:  https://a.co/d/0dNb2L9I

Please consider purchasing the book and if you find it informative and helpful in moving us closer to resolving this issue, share the link with friends, family, and influential people on this issue in Congress and in your state and local government.  Thank you, Dan Gallagher

Wake Up, America: Minneapolis and the Escalation We Pretended Wouldn’t Come

The death of Renée Nicole Good in Minneapolis is tragic. A life ended suddenly and violently, and no decent person should be indifferent to that. Almost immediately, the country split into familiar camps, each racing to advance a narrative before the facts had settled. As usual, nothing was learned, and tensions only rose.

Whatever the final legal findings say, one thing is already clear: this event did not occur in isolation. It fits a pattern that has been building for years. We can keep pretending these are isolated incidents, or we can face what the evidence is telling us. The divide over immigration enforcement is producing predictable—and preventable—tragedies.

The Data Tells a Story

Immigration enforcement happens in two fundamentally different ways. In cooperative jurisdictions, when local police arrest someone for an unrelated crime, ICE can lodge a detainer—a request to hold that person briefly so ICE can take custody when local charges are resolved. The transfer happens inside a jail, controlled and administrative. In non-cooperative sanctuary jurisdictions, local authorities refuse these detainers. This forces ICE to locate and arrest people in the community—at homes, workplaces, during traffic stops, and on streets. One method happens behind secure walls. The other happens in public—where crowds form, tensions escalate, and split-second decisions can turn deadly.

Between January 20 and October 15, 2025, ICE made more than 217,000 arrests in the country’s interior (Prison Policy Initiative analysis of ICE data). The majority of those arrested had either prior criminal convictions or pending criminal charges, while approximately 33% were arrested for immigration status violations only. It is not known how many individuals in this latter category were arrested in conjunction with another arrest or were subject to final deportation orders.

After Maduro: The Test of U.S. Power, Restraint, and Competence

This is Part III of a three-part series examining the Trump Administration's Venezuela strategy. Part I established why the Western Hemisphere became a U.S. national security priority. Part II explained how that strategy translated into Operation Southern Spear and the military force posture now in the Caribbean.

In the early hours of January 3, 2026, the United States conducted military strikes across Venezuela and captured President Nicolás Maduro and his wife, transporting them to the USS Iwo Jima before transfer to face narcoterrorism charges in the Southern District of New York. Operation Absolute Resolve succeeded with no U.S. casualties or equipment losses.

For readers of this series, the question was never whether this would happen—it was when, and what would follow.

In a press conference today, President Trump provided the answer. Asked who would govern Venezuela, he stated simply: "We are going to run it." He clarified that the United States has no intention of executing this operation only to hand authority immediately to officials who may lack capacity or support. The U.S. will establish stability, begin reconstructing the oil industry, and only then identify Venezuelan leadership capable of assuming power.

This represents direct U.S. interim administration—not immediate transfer to Venezuelan opposition figures. It is a significant departure from recent interventions and raises profound questions about execution, timeline, and exit strategy.

From Strategy to Enforcement: What the U.S. Is Doing in the Caribbean

This is Part II of a three-part series examining the Trump Administration's Venezuela strategy. Part I established why the Western Hemisphere became a U.S. national security priority.  Part III examines the removal of Nicolas Maduro and its implications for the future of Venezuela.

The current U.S. military presence in the Caribbean cannot be understood in isolation. What some observers perceive as a sudden escalation is, in fact, the operational expression of a strategic shift articulated years ago and formalized in the 2025 National Security Strategy. 

From Policy to Force Posture

Operation Southern Spear is the most visible manifestation of this change. Announced shortly after President Trump’s January 2025 inauguration, Southern Spear is led by U.S. Southern Command and the Navy’s Fourth Fleet. While it builds on earlier counter-drug and maritime security efforts, including experimentation with manned and unmanned systems, it has undergone a significant expansion in scope, persistence, and enforcement authority over the past six months.

What the Force Is—and Is Not

The U.S. has now assembled a substantial joint force under Joint Task Force Southern Spear: a carrier strike group, an amphibious ready group with a Marine Expeditionary Unit embarked, supporting surface combatants, special operations elements, and forward-deployed airpower operating from Puerto Rico and regional bases.

This is not an invasion force. It is a control force—designed to deny freedom of movement, disrupt logistics, impose costs, and shape outcomes without occupying territory.