With Russia’s invasion of Ukraine, war–even the possibility of nuclear war–is once again on our minds.
For centuries, Christendom has considered the moral issues around warfare in terms of the “just war” theory. St. Augustine coined the term and St. Thomas Aquinas set forth three requirements:
First, the war must be waged upon the command of a rightful sovereign. Second, the war needs to be waged for just cause, on account of some wrong the attacked have committed. Thirdly, warriors must have the right intent, namely to promote good and to avoid evil.
- the damage inflicted by the aggressor on the nation or community of nations must be lasting, grave, and certain;
- all other means of putting an end to it must have been shown to be impractical or ineffective;
- there must be serious prospects of success;
- the use of arms must not produce evils and disorders graver than the evil to be eliminated .
Today, though, the very concept of a just war is being challenged. This is true particularly in the Roman Catholic Church. Pope Francis himself told the the Russian Orthodox Archbishop Kirill,
There was a time, even in our Churches, when people spoke of a holy war or a just war. Today we cannot speak in this manner. A Christian awareness of the importance of peace has developed. Wars are always unjust since it is the people of God who pay. Our hearts cannot but weep before the children and women killed, along with all the victims of war. War is never the way.
I think that the just war theory is still useful, but it does have problems. Not that every war is unjust, so that the only alternative is pacifism, as the Pope and some Catholics seem to be pursuing. Rather, the various criteria are so open to interpretation that all sides can claim that justice is on their side, so that the doctrine does not give clear guidance. Furthermore, the criterion of “serious prospects of success” mandates surrender when smaller countries and outgunned forces face a militarily superior aggressor. Such a teaching encourages, rather than limits, military aggression. On the face of it, this would have meant that Ukraine should have not resisted Russia’s invasion, since the prospects of their success in battling what looked like, on paper, to be a vastly superior military force, seemed to be slim. A better teaching on war would encourage the kind of resistance and heroism that has surprised the world.
I would urge Christians, Catholic and otherwise, who are struggling with the moral issues surrounding war, to consider the contributions of Martin Luther, who goes beyond the “Just War” theory to contribute to Christian reflections on war in a significant way. (What follows derives from and is developed in more detail from my book Christianity in an Age of Terrorism, (2002), pp. 122-130, which, though dated, remains highly relevant today.)
Luther opposed Crusades, which occasioned Rome’s doctrine of indulgences, and the very concept of “holy wars,” such as the jihad of the Turks that was threatening Europe in his day and that motivates Islamic terrorism today. He was also against the moral checklist approach to ethics that, he thought, served to rationalize sin and promote self-righteousness. He also opposed the wars of conquest that were endemic among the European rulers of his day (including the popes), who were seemingly undeterred by the church’s just war theology.
Luther’s teaching on the morality of war is simple, succinct, and easily applied: “Whoever starts a war is in the wrong.”* But there are “wars of necessity.””Whoever starts a war is in the wrong.”* But there are “wars of necessity.”
Wars launched intentionally and deliberately are from the devil. But countries that are attacked are engaged in what Luther called a “war of necessity.” In those cases, rulers are obliged to defend their people with the sword.
In his book The Ethics of Martin Luther, p. 137, Paul Althaus summarizes Luther’s teachings about war:
Implicit in what Luther says is that he recognizes only a defensive war which is forced upon us by an aggressor. War is right only when it is “our only miserable way of defending ourselves.” Luther knows that most wars are waged for quite different reason: selfish motives of princes and lords, lust for the property and possessions of others, desire for glory, the feeling that our honor has been insulted, wrath, and the desire for revenge. However, a Christian prince is forbidden to wage war for such reasons. The one and only purpose of a war must be to protect his subjects against attack. In this sense the decision to go to war and the decisions about how war is to be waged must be quite “simple.”
The notion that only defensive wars are morally legitimate does not solve all controversies. Contending countries often both claim that they are just defending themselves. But, by this criterion, Russia is waging an immoral invasion, and Ukraine is justified in defending itself. That doesn’t mean that we should go to war with Russia. Our invasion of Afghanistan and Iraq, would not be justified, since we started those conflicts, though responding militarily in a focused way to Al Qaida’s 9/11 attacks would be. So would America’s involvement in World War II, though possibly not World War I.
I suspect Luther would approve of mutual defense pacts, such as NATO, though not if the nations so allied would join in a war of aggression. And he would recognize, in the messiness of life, that war is especially messy, that sin taints everything, and that the only purely valid justification we can find is in Christ.
*Quoted from “Whether Soldiers Too Can Be Saved,” Luther’s Works, 46:117.
Illustration: Soldiers in Battle via publicdomainvectors.org, public domain
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