At the Christianity and National Security Conference in Washington, DC, Nigel Biggar, Daniel Strand, and Marc LiVecche participated in a panel discussion about the just war tradition. Biggar covered the tradition for today while Strand talked about Paul Ramsey’s contribution and LiVecche explained Reinhold Niebuhr’s relationship with the tradition. The following is a transcript of the lecture.
Nigel Biggar: Thanks very much, Mark. Can you hear my voice at the back? Great. Thank you for the invitation to speak at this event, which aligns closely with my own interests. I’m glad to contribute to your reflections. My aim is to speak for no more than 20 minutes, leaving 10 minutes for Q&A. I know we’re starting 12 minutes late, so I want my full 30 minutes.
The title of my reflections is “Wishful Thinking or Nettle Grasping?” Let me take you back about 10 years. I need to confess, as part of the preface, that I supported the invasion of Iraq, and I’m not entirely clear whether I’ve found a reason to stop supporting it—put that aside. Many of you will likely disagree; put that aside. Ten years ago, I gave a talk in Oxford on this subject. A friend, a Baptist minister, stood up afterward and said, “There had to be a better way.” I thought, maybe there was, but why did there have to be a better way?
Another example: last Sunday, I gave a sermon at Christ Church Cathedral in Oxford on immigration policy. Normally, I speak from scripture, but this time I addressed immigration. I said, as a rule, economic migrants should be returned home. As a Christian who takes the Bible seriously, I understand our duty of care to vulnerable migrants. Deuteronomy 10:19 says, “You shall also love the stranger, for you were strangers in the land of Egypt.” I get that. But we must distinguish political refugees and war refugees from economic migrants seeking a better life. My view is that, as a rule, economic migrants should be returned home.
Why? If illegal economic migrants are not returned, immigration laws become meaningless, effectively creating open borders. While open borders might seem acceptable, large-scale immigration can disrupt societies, create conflict, and foster lucrative markets for human trafficking. It can also deprive sending countries of talent. For instance, three years ago, 40% of Syrians with graduate degrees lived in Germany. That’s detrimental to Syria’s future. Large-scale economic migration presents multiple problems. Migrants often pay significant sums and take extraordinary risks to reach Europe or Britain. Returning them home will be distressing, but is there a better way? I can’t see it.
Those outside government can wring their hands and agonize, which is appropriate. But those in government must make decisions; they must grasp the nettle. I’ve never been in government. As an academic, I’ve chosen a career that avoids hard decisions. I reflect and spectate—much safer. But I deeply admire those who take another path and make the hard decisions. For instance, in discussions about war, a friend used the term “war machine.” I said, “When you say ‘war machine,’ I see the faces of friends in the military and government, who are as morally sensitive as you, perhaps more so, and who are on the front lines while you are not. Let’s talk about individuals making these decisions.”
Christians who care deeply must stop wringing their hands at some point and start grasping nettles. We must engage as God did by coming down from heaven, taking on human flesh, with all its limitations, tensions, and vulnerabilities, in Jesus Christ. If you want a theological basis for nettle-grasping, consider the incarnation. I’ve prepared a handout with quotations I’ll read. If you’d like a copy, let Mark know.
First, the moral duty to grasp nettles falls on some, and the rest of us must respect that necessity, even if we don’t do it ourselves.
Now to Christian just war thinking—a brief overview. Jesus and his disciples came from the ruled class, not the rulers. They were not part of the elite. Thus, the nettle-grasping required of those with public responsibility wasn’t required of them. In the 4th century, Christianity was tolerated in the Roman Empire and eventually became the established religion. By the early 5th century, we find St. Augustine, Bishop of Hippo in North Africa. Bishops then weren’t just pastors but also civil judges, tasked with deciding cases and declaring sentences. Augustine, dragged into the bishopric against his will, was compelled to make hard public decisions.
In 408, Augustine wrote to Paulinus of Nola:
“On punishing or refraining from punishment, what am I to say? Our desire is that whether we punish or refrain, it wholly contributes to their security. These are deep and obscure matters. What limit ought to be set on punishment regarding both guilt and the wrongdoer’s strength of spirit? What should each suffer? What do we do when punishing one person leads to their destruction, but leaving them unpunished destroys another? What trembling, what darkness!”
He quotes Psalm 55: “Trembling and fear have come upon me, and darkness has covered me. I said, ‘Who will give me wings like a dove, so I can fly away and be at rest?’” I first read that passage as a history undergraduate in 1976. It marked the rest of my life. Augustine wanted to fly away but didn’t. I deeply admire that.
Three years later, Augustine corresponded with Christian military tribunes responsible for law and order, often using lethal force. In a letter to Flavius Marcellinus around 411, Augustine responded to the question of how Christians could hold public responsibility in light of the Gospel’s commands to forgive and not retaliate. Augustine made an important move in Christian thought. Reflecting on Romans 12:17, he wrote:
“What is it, not to return evil for evil, except to refrain from a passion for revenge? People can often be helped against their will by being punished with a sort of kind harshness.”
Augustine argued that moral action hinges on motive, not merely the act. One can do physical harm, even kill, but without knowing the motive, we cannot judge whether it was right or wrong. For Christians, physical force—including lethal force—is forbidden if driven by vengeance. But depending on circumstances, it may be permitted if not vindictive.
Augustine stands at the head of the Christian just war tradition. In the 13th century, Thomas Aquinas systematized Augustine’s ideas. In the 16th century, Spanish theologians like Francisco de Vitoria and Francisco Suárez further developed them. In the 17th century, Hugo Grotius, a Dutch Protestant lawyer, contributed. Since World War II, Protestant theologian Paul Ramsey and others have revived just war thinking. This tradition helps Christians grapple with difficult moral questions in war.
Let me introduce some criteria from the just war tradition. There are two sets: one governs decisions about going to war, jus ad bellum, the other governs conduct in war, jus in bello.
For jus ad bellum, key criteria include:
1. Just cause: There must be a grave injustice requiring rectification. This isn’t primarily self-defense but addressing serious wrongdoing.
2. Right intention: The aim must be to rectify the injustice, not ulterior motives like acquiring resources.
3. Last resort: War is only permissible if peaceful means have been exhausted.
For jus in bello, two key criteria are:
1. Proportionality: The military means used must be proportionate to the goal.
2. Discrimination: Combatants must distinguish between combatants and non-combatants, avoiding intentional harm to civilians.
Just war is not holy war; it’s a war deemed morally justified, all things considered. Like all human endeavors, war involves moral flaws. Even just wars are waged by sinners. For example, during World War II, President Roosevelt used deceptive tactics to persuade Americans to enter the war. He misrepresented a naval incident and promoted a fabricated map showing Nazi plans for Latin America. Despite these flaws, the war against Hitler is widely seen as justified.
Finally, a brief note on national interest. Just war addresses grave injustices, often framed as humanitarian intervention. Yet, for interventions like Iraq or Afghanistan, governments must appeal to national interest. It’s legitimate for citizens to ask why their nation should bear the cost of addressing injustices abroad. National interest is not inherently selfish. Pursuing legitimate self-interest is a duty. French political philosopher Yves Simon wrote during the 1935 Abyssinian Crisis: “What should we think of a government that ignores the interests of its nation?”
Consider Edmund Burke, who supported American colonists but later urged British intervention in revolutionary France. Critics asked why Britain should focus on Paris and not the Barbary corsairs in North Africa. Burke replied: “Algiers is not near, not powerful, not our neighbor, not infectious.” Revolution in Paris threatened British national interest; piracy in North Africa did not.
I’ll leave you with these reflections.
Q&A / Remarks
Mark LiVecche: Thank you, Nigel. Just to give you a heads-up on how this will run: Dan and I will have remarks to follow, about 10 minutes each, focusing on this question of nettle-grasping. For now, rather than moving directly to another set of remarks, if there are questions for Nigel, please ask them now. We might not get through all of them; at some point, I may interpose myself to give my remarks and set up further discussion. Feel free.
Question: Thank you. I’m Dan from New York. I was interested in how you define “economic migrant.” Since so much of U.S. history involves people coming for economic reasons, how do you distinguish between economic migrants and those in genuine need? I’m thinking of the Irish potato famine, where economic policies caused massive immigration to the U.S., and of Haiti today, where dire circumstances, mostly economic, drive many to seek a better life.
Nigel Biggar: That’s a good point. You’re right—on the one hand, you have asylum seekers fleeing civil war or failed states. In cases of dire need, it seems we must help as best we can. There are different ways of doing that. For example, the European Union and Britain spend significant resources stabilizing states in Africa and along the Mediterranean.
On the other hand, you have people desperate for a better life. I grant that distinguishing between these groups is difficult, and we must develop criteria to do so. But open borders cannot be the solution. We know what happens when societies are overwhelmed by hundreds of thousands or millions of migrants. That’s what happened to native peoples in North America. Open borders can destabilize societies.
Each case must be judged on its own merits. Different nations at different times are capable of absorbing more or less, and thus of being more or less generous. But even then, difficult decisions are unavoidable. My bottom line is that we cannot make ourselves responsible for everyone’s fate; we simply lack the power to do so.
Compassion is good, but it must look in more than one direction. Compassion for the migrant is essential—migrants often take great risks and pay significant sums to seek a better life. But we also need compassion for the working class in my own country. For someone like me, a middle-class person, immigration means interesting restaurants, polite baristas, and cheap home help. For the working class, it can mean job competition, housing scarcity, and employers who avoid training local workers because they can hire cheaper migrant labor.
Finally, we must also have compassion for government officials making these difficult decisions. But I take your point: distinguishing between types of migrants requires careful thought, and generosity will vary depending on the situation. Thank you.
Question: I’m Christopher from the Southern Baptist Theological Seminary. You gave an interesting intellectual history of the just war tradition. Many figures you mentioned are also central to the natural law tradition. To what extent do you think natural law and just war run together? Does just war find its best home in the natural law system of ethics?
Nigel Biggar: Since Thomas Aquinas, in the Roman Catholic tradition, they have historically run together. Augustine, however, does not engage much with natural law. That said, there have been Protestant just war theorists, such as Grotius, Paul Ramsey, and Oliver O’Donovan, who do not rely heavily on natural law thinking.
The two traditions are not conceptually wedded. Whether just war theory finds a more natural home within natural law is an open question. John Keown has probably written on this and could provide further insight.
Question: The just war tradition includes rules outlining what makes a war just. But couldn’t those same rules be used by other countries—our enemies, even—to justify wars against us? What makes our side different? Is there a sense in Christian just war theory that God ordains our reasons for war?
Nigel Biggar: Thank you. Yes, anyone can use moral justifications for war, and everyone does. The Chinese Communist Party, for example, wouldn’t use the criteria of just war thinking rooted in the Latin West. But just war principles have influenced the international laws of war.
You’re right: in recent conflicts like Iraq and Afghanistan, just war theorists have argued both sides of the debate. Just war theory doesn’t provide definitive answers but offers intellectual tools for working through difficult decisions.
The fact that opposing sides use the same framework doesn’t mean their cases are equally strong. Even bad actors seek moral justification for their actions. For Christians, just war theory provides principles and criteria compatible with our fundamental beliefs, enabling us to make morally informed decisions.
Question: Thanks for your talk. What would you say to someone who asks why Christians should get involved in policymaking or statecraft, given the morally messy choices involved—like deporting migrants or causing civilian casualties in conflict? Why not live peaceful, quiet lives and avoid those spheres altogether?
Nigel Biggar: Did everyone hear the question? Yes? The question is: why should Christians get involved in the messy, morally hazardous work of government? Why not live peaceful lives?
My answer has two parts. First, since we live in a fallen world, peaceful lives are only possible within ordered societies. Order requires curbing others’ harmful tendencies. Not everyone can be persuaded by reason to refrain from wrongdoing, so force must sometimes be used. In other words, your peaceful life is made possible because others are willing to use force.
Second, if others must dirty their hands to maintain order, why shouldn’t you? Different people hold different political views. Some believe more pacifistic Christian communities could influence the world toward greater peace. I don’t share that view. Thank you.
Mark LiVecche: Fantastic, that is an excellent transition to what I want to do. Can you hear me in the back? Thumbs up. I’ll act as a bridge between this discussion on grasping nettles and what Dan Strand will bring—a solution to some of the hazards of nettle-grasping. Even among Christians advocating for nettle-grasping, there are differing perspectives.
One such perspective comes from Reinhold Niebuhr. I won’t say much about him now, as Colin Dueck will cover him later. First, we owe Niebuhr a debt of gratitude. Without him, Providence Magazine wouldn’t exist; its foundation draws inspiration from Niebuhr and his brand of Christian Realism. However, Niebuhr is problematic, and I’ll illustrate why. Dan will then offer a solution to his shortcomings.
Niebuhr’s key contribution was his effort to persuade the mainline church to support U.S. intervention against Hitler. After Pearl Harbor, he wrote Our Responsibility in 1942, where he welcomed America’s forced departure from isolationism, stating that we had been “thrown into a community of responsibility” because we had been “overcome by a community of sorrows.” Responsibility is central in Niebuhr’s thought, but it comes at a cost.
Niebuhr wrestled with pacifism. Before World War I, he was a pacifist. The war unsettled him, leading him to support U.S. intervention. After the war, he declared he was “done with the war business.” In the lead-up to World War II, Niebuhr again pushed for intervention, ultimately abandoning pacifism. Yet, he never fully let it go. Niebuhr remained, in his words, a “pacifist willing to kill.”
Niebuhr believed the supreme Christian law was the law of love, equated with non-resistance to evil. This encompassed physical violence, coercion, and hostility. Yet, Niebuhr recognized that absolute non-resistance leads to irresponsibility and calamity. To avoid catastrophic outcomes, Christians must assume responsibility, which sometimes involves “dirtying their hands.”
Niebuhr’s dilemma: “Killing is wrong, but in a just war, it is necessary.” This tension is central to his thought. Consider Timothy Kudo, a former U.S. Marine officer. Though he never pulled the trigger, he authorized actions resulting in deaths. Kudo describes the moral dissonance of moving from the civilian ethic of “thou shalt not kill” to a military ethic where success is measured by killing. This shift shattered his self-perception as a “good person.”
Kudo recalls a specific incident: the accidental killing of two unarmed Afghan teenagers. Marines followed protocol but misinterpreted the situation, resulting in a tragic mistake. Yet, lawful killing can haunt warfighters as well. William Manchester, in his memoir *Goodbye, Darkness*, recounts killing a Japanese sniper. Despite the sniper’s lethal threat, Manchester was overwhelmed by the intimate humanity of the act, breaking down in tears, vomiting, and losing control of his body. His memoir reads as a quest for absolution.
Many warfighters seek not only forgiveness but vindication. Forgiveness implies wrongdoing; vindication affirms rightful action. Some killings—murder—are inherently wrong. Others, such as accidental or justified wartime killings, are morally permissible, even obligatory. Niebuhr’s framework offers no space for moral vindication in war. His insistence that “killing is wrong, but necessary” burdens warfighters with moral injury.
Moral injury, unlike PTSD, stems from a perceived violation of one’s moral code. Studies link moral injury, particularly from killing, to higher rates of veteran suicide. Niebuhr’s view has made warfighting inherently morally injurious, a calamity for our military. I propose distinguishing moral injury from moral bruising. Bruises, though painful, are non-debilitating. Augustine speaks of the “sorrows of combat,” emphasizing that war should weigh heavily on the soul. However, not all wartime killing warrants moral injury; some require vindication. Niebuhr’s framework cannot provide this.
Who will offer a better solution? Enter Dan Strand.
Daniel Strand: Thank you, Mark. As Mark mentioned, I’ll discuss Paul Ramsey, a contemporary of Niebuhr and a key figure in Christian ethics. Before I begin, let me note that I work for the Department of Defense, but my remarks here are personal and do not necessarily reflect the views of the U.S. government.
We’re talking about nettle-grasping and dirty hands—the wicked problems inherent in governance, especially in defense and foreign policy. These problems are complex, with no clear or clean solutions. Afghanistan, for example, offers no perfect answers; any course of action involves tragedy and loss. Such challenges are inherent to international politics and defense, and anyone entering these fields must be prepared to navigate them.
Christian Realism begins with the world as it is—messy and broken. Ramsey, a Christian realist and ethicist at Princeton, engaged deeply with these realities. Unlike Niebuhr, Ramsey was less publicly visible but profoundly influential, particularly in reviving the just war tradition among Protestants.
Ramsey diverged from Niebuhr on a crucial point: the relationship between love and responsibility. While Niebuhr saw them as competing principles, Ramsey insisted they were integrated. For Ramsey, love is the guiding norm for all aspects of life, including politics and warfare. Acting responsibly in war, according to Ramsey, can be an act of love.
This perspective allowed Ramsey to navigate the complexities of war without Niebuhr’s moral ambivalence. He argued, for instance, for a moral basis for nuclear deterrence—a controversial position but one grounded in his conviction that love could manifest even in the harsh realities of statecraft. Similarly, he supported U.S. involvement in Vietnam, seeing it as a necessary, if tragic, act of love.
Ramsey’s approach emphasizes the complexity of reality, requiring thoughtful wrestling with difficult moral questions. His work demonstrates that love, rightly understood, can guide even the most challenging policy decisions. With that, we’ll open the floor to questions.
[Applause]
Mark LiVecche: I’m going to make one very brief comment and then let Nigel add a couple of thoughts. My brief comment is this: if you want to appear on the cover of Time Magazine, write like Niebuhr; don’t write like Paul Ramsey. That’s my comment. Nigel will now give a few comments, and I hope to stir the waters a bit by asking him to touch on the difference between moral and non-moral evil, and why that distinction might be significant.
Nigel Biggar: That was exactly what I was going to address. Just a couple of thoughts. First, Mark mentioned cases of people finding killing deeply psychologically disturbing. It struck me that agonizing over killing is something Christians should do. However, it’s important to note that this isn’t universal. There are societies where killing isn’t seen as morally troubling. I recently read about Somaliland in the 1940s. The author described African tribesmen whose primary purpose was to be warriors. For them, killing the enemy was not something to regret but something to celebrate. The intense psychological struggle over killing, common in Western, Christianized societies, isn’t universal. Yet, for those of us shaped by Christian ethics, even those called to kill will agonize over it, as they should.
Second, we’re diving deeply into just war theory because it exemplifies the broader Christian wrestling with the problem of grasping nettles. While war is among the sharpest and most difficult nettles, the same moral challenges arise in other domains like immigration policy.
Third, there are situations where achieving good or doing right is impossible without causing harm. You might say, to do good, you can’t avoid doing evil—or, if you’re a Lutheran, you might say, you can’t do right without doing wrong. I’m not a Lutheran; I find that language confusing. I prefer to speak of pursuing the good while causing non-moral evil. Here, “evil” means harm or damage, not immorality. For example, to save innocents, you may have to kill aggressors. The killing constitutes harm but is not immoral if done with the right intention. The act remains morally right despite causing harm. That’s the dilemma we’re addressing.
Mark LiVecche: Would you say a Christian should ever commit moral evil?
Nigel Biggar: No, I wouldn’t. Christians should avoid moral evil. However, what counts as morally wrong can often be contentious.
Mark LiVecche: All right, we have time for a few questions, comments, or rebukes. Please feel free to come to the microphone.
Question: My name is Ethan from Wheaton College. I think you said, “The metric for success in war is killing.” Could you explain that?
Mark LiVecche: My name is Mark LiVecche. Just to clarify, my metric for success isn’t killing. Timothy Kudo spoke of the paradox of killing in war. For him, the moral rule is “Thou shalt not kill,” with no distinction between killing and murder. Yet, in combat, to bring the war to a successful conclusion, he recognized he had to kill the enemy. This created a moral dissonance for him, leaving him unable to reconcile doing what he believed was wrong with the necessity of war.
Nigel Biggar: I agree, Ethan. In just war, the metric for success isn’t killing but breaking the enemy’s will to fight. Killing may serve as a means, but if the enemy surrenders, you’ve achieved success without further killing.
Speaker: As a Marine, I’d add that for a platoon commander, success in the immediate context of combat often looks like eliminating the enemy. That’s a tactical metric, distinct from the broader strategic goal.
Daniel Strand: That’s an important distinction. At the strategic level, the goal is to end the conflict. At the tactical level, in the heat of battle, success might indeed hinge on eliminating the immediate threat.
Question: Hi, I’m Katherine from Liberty University. You’ve discussed justice before war and during war, but what are your views on jus post bellum?
Mark LiVecche: If just war theory were a computer interface, you’d click on jus ad bellum, and under “Right Intent,” you’d find jus post bellum. The end of a just war is peace, and under “Right Intent,” you’d define what peace should look like in the specific context. It might mean outright victory, surrender, or something else, like getting Assad to stop gassing his people. Some, like Eric Patterson, argue for *jus post bellum* as a distinct category. I prefer to keep it under “Right Intent” to avoid overcomplicating the framework.
Nigel Biggar: The push for jus post bellum as a distinct category stems from experiences like Iraq, where post-war planning failed. Conceptually, however, it’s already part of the system. Peace is the goal of just war, so you must think about what kind of peace you aim to achieve and tailor the war accordingly.
Mark LiVecche: As a caveat, you can’t always predict what peace will look like. For example, I’ve argued that dropping the bomb on Hiroshima led to the peace we now enjoy with Japan. Achieving peace can sometimes involve morally complex decisions.
Question: Hi, I’m Greg Wiggle from the University of Dallas. How do we approach foreign policy with non-Christian nations without it being perceived as cultural imperialism? And can just war be considered a form of charity?
Nigel Biggar: Yes, just war can be seen as an act of charity. Aquinas and Augustine frame it as such, with love guiding the use of force. Ramsey similarly treats just war as an act of love. However, applying this principle requires understanding the context, as what appears uncharitable from a distance may actually be a rescue.
On cultural imperialism: Simply presenting your ideas isn’t imperialism. It’s sharing your perspective. If the other party disagrees, you negotiate. Finding common ground doesn’t require imperialism. Even in discussions of war ethics, there are often parallels across cultures, such as between Western just war thinking and Confucian ideas about war.
Question: My name is Sean Kim from Wheaton College. What should Christians do if their nation engages in an unjust war? Should they submit to authorities or resist?
Nigel Biggar: Christians are accountable to God through their conscience. If convinced the war is unjust, they have a democratic right to protest. Those in government or the military may need to resign. However, determining the morality of a war is rarely clear-cut. Sometimes, one must give the benefit of the doubt to leaders with access to more information.
Mark LiVecche: Christians must consider the regime’s nature before enlisting. In cases like Nazi Germany or apartheid South Africa, Christians should not serve in their militaries. Once in uniform, I don’t believe in selective conscientious objection; it would undermine military cohesion. Conscientious objection should be for those opposed to all wars.
Daniel Strand: Ramsey emphasizes that the Church acts as a theoretician in politics, often making pronouncements without full information. Christians should approach these matters with humility, recognizing the complexity and the burden on policymakers.
Question: I think we can all agree that war should be a last resort. What criteria determine when war is a reasonable last resort?
Nigel Biggar: Good question. Assume the issue involves grave injustice. You’ve tried diplomacy, sanctions, and other non-violent measures. If your adversary continues negotiating in bad faith—like Hitler—it may become clear that war is unavoidable. The rule is that war should be the last realistic option after exhausting all alternatives.
[Applause]