Just War Principles in Ukraine

Representatives of the U.S. and Russian governments are meeting in Saudi Arabia as I write. Their goal is to determine whether an agreement can be reached to end the war in Ukraine. I’m grateful that this effort is being made.

Two years ago, I expressed skepticism of the American and European governments’ claim that, with enough support, Ukraine could defeat the invading Russian army and reclaim all its territory (“Peace in Ukraine,” April 2023). I observed that, if my suspicions were true, then just war theory counseled negotiations to bring an end to hostilities.

The just war tradition requires us to determine just cause, but it also asks us to ponder the probability of success, among other criteria. At that time, I wrote, “It may be gallant to fight what one knows is a losing battle, but according to just war teaching, doing so reflects pagan vanity, not Christian moral judgment. A wise leader does not embark on unrealistic enterprises, especially when lives are at stake.”

The last two years have vindicated my skepticism. Soon after I wrote my column in 2023, the press hyped a Ukrainian counter-offensive. It failed. The Ukrainian and Russian armies remained locked in a grinding war of attrition. Through it all, the Biden administration maintained the official stance of supporting a Ukrainian victory, which was defined as reclaiming all lost territory. Again, this sounds high-minded and gallant. But one does not occupy the moral high ground by sacrificing the lives of soldiers in pursuit of unrealistic objectives. Biden officials have admitted that they did not believe the Ukrainians could triumph, even as their official stance suggested they did.

The Trump administration has changed course. The president has determined that the Ukrainians cannot defeat Russia’s army. In light of this judgment, Trump is pursuing the normal means by which inconclusive conflicts are resolved: negotiated compromise. His motive may be to secure the best outcome for America’s interests, rather than attaining a moral end. But the effect is similar: cessation of hostilities when there is little probability of resolution on the battlefield.

Many commentators insist that Ukraine could have prevailed—if the Biden administration had had greater resolve and been willing to provide more advanced weapons and other supplies. They insist that Trump is betraying Ukraine, because he, too, could ensure victory, if only he would commit the full might of American power to the cause.

I don’t wish to debate weapons systems. Rather, I want to draw attention to political realities. As JD Vance indicated in his speech at the Munich Security Conference, European leaders lack a democratic mandate. They certainly lack a mandate to intensify their involvement in Ukraine. In the United States, Trump won in part because he promised that, far from increasing U.S. involvement in Ukraine, he would end the war.

Assessing the probability of success requires more than measuring military throw weight. War is undertaken by nations. Indeed, it is a maker and breaker of nations. It is a foolish leader who ventures more than his followers will support. Biden was not foolish in this regard, nor are the present array of European heads of state, many of whom rushed to denounce Trump’s negotiations with Putin, but none of whom is willing (or able) to commit to military involvement. Their citizens do not want it, and they lack the means. (A retired British general reports that the UK can field only one battle-ready armored brigade.)

Critics are sure to announce that Trump has “handed Putin a victory.” They’re already doing so. This is absurd. Putin won a victory, however partial and costly. To think otherwise requires self-delusion. The United States does not have the means to deny Putin his victory. This is a political assessment, not a statement about how many cruise missiles we could launch at Moscow. 

So, I return to the moral principles of just war. Among them is the following: It is immoral to unleash the violence of war when objectives cannot be achieved, however just those objectives may be. The Ukrainian army is unable to bring an end to hostilities by achieving victory. The nations of the West are unwilling to enter the fray with sufficient force and commitment. These seem to be indisputable facts. Moral reasoning must reckon with realities. Trump’s thinking is far removed from reflection on just war theory. But he is acknowledging reality and taking the steps necessary to put an end to a war that cannot be won. No doubt many mothers and fathers whose sons have died in the last two years of fruitless combat may have wished that the negotiations in Saudi Arabia had taken place in 2023. 

This article is excerpted from the Public Square column in the forthcoming April issue.