Just War and Just Peace

As the Ukraine War passes another milestone, can any war be considered just? Christine Schliesser explores Just War theory and a possible path to Just Peace.

Christine Schliesser

Christine Schliesser lectures in Theology and Ethics at Zurich University, and is a scientific collaborator with the Center for Faith & Society at Fribourg University.

Civilian evacuation across Irpin River during the Ukraine War.

Yan Boechat/VOA via Wikimedia Commons.

Will Germany deliver Leopard 2 tanks to Ukraine? No? Yes? When? Media discussion of the war that the Russian Federation started against Ukraine in 2014 and that entered a new stage one year ago, currently centres on questions of weaponry. Who else will send tanks? And what about fighter aircrafts? No? Yes? When?

In classical military ethics, which has long been dominated by the so called Just War Theory, these questions fall under ius in bello, the right conduct in war. This also includes discussions on proportionality, military necessity and the differentiation between combatants and non-combatants.

Just War Theory has a long tradition in Christian thought. Church Father Ambrose argued that whoever does not ward off injustice from his fellow man (or woman for that matter) when he can, is as guilty as he who commits it. Ambrose’s student, Augustine, then developed this thought in more detail as he laid the foundations for what could be called a bellum iustum, a just war.

Even before going to war, the criteria of the ius ad bellum, the right to go to war, must be satisfied. These include, for instance, a just cause, legitimate authority, prospect of success, right intention and last resort. We encounter these criteria again in slightly modified form in our modern international law. In view of these guidelines, of Russia’s breach of international law, and of Ukraine’s right to self-defence, the on-going war in Ukraine clearly seems to be a just war. Or is it?

Nothing holy or just

Two points need to be made in this discussion. Firstly, there are no just or holy wars. Period. Or as 150 churches, after the horrors of the Second World War, put it in Amsterdam in 1948: ‘War is contrary to the will of God.’ Wars are always an evil and an expression of the failure of human beings to strive for peace. This also holds true for the war in Ukraine. And this means that we need a new dimension in the debate, namely guilt.

Every action – and inaction – here involves guilt. As the German pastor Dietrich Bonhoeffer, who was killed by the Nazis for his engagement in a plot against Hitler, put it:

‘everyone who acts responsibly becomes guilty’.

And even if we become guilty for the sake of the other person, our guilt remains just the same. Yet, as Bonhoeffer concludes, we trust in the grace of God, who calls us to responsible action. , Bonhoeffer’s ideas have been considered dangerous and easily misused to justify any crime, as forgiveness is always available. Nevertheless, we must acknowledge the reality of guilt that pervades any war, including the war in Ukraine.

Just Peace

Secondly, recent years have seen a new kid on the block: Just Peace Theory. While Just War Theory looks at a conflict from the perspective of violence, Just Peace Theory puts the focus on peace. This includes adding a third set of criteria. Ius post bellum looks at justice after a war. We know that after a conflict is before a conflict. We therefore need to pay more attention to what happens after the weapons finally fall silent.

Here, the experiences of truth and reconciliation processes worldwide can help. Both dimensions belong inseparably together and both already begin during a conflict, not just after it. Truth, for example, requires the documentation of war crimes committed by all parties to ensure the prosecution of war criminals later on. And reconciliation is the conditio sine qua non for sustainable peace.

Russia’s war against Ukraine and its threats against NATO and Western countries demonstrate, not least that after the end of the Cold War, opportunities for genuine and sustainable reconciliation were missed as latent hatred, prejudices and stereotypes were allowed to linger.

Just Peace Theory emphasizes that building peace is an art and a craft. It requires specific skills, training and preparation. It also requires virtues of grace, persistence and forgiveness, Countless documented examples world-wide supply empirical proof that these methods actually work. Perhaps it is worth devoting some of the $2,113 billion (2021) of global annual military expenditure for training non-military approaches to address conflict resolution? To learn how to build peace as much as how to wage war? No? Yes? When?

Pathways to Peace

One such initiative is Pathways to Peace. Aiming at peace, justice and reconciliation in times of war, this initiative is currently being developed through the Conference of European Churches, a group of some 120 member churches in 38 countries. With their long-term involvement and intimate knowledge at the grassroot level, faith actors in civil society seem uniquely positioned to connect people, heal relationships, offer a new social imaginary and facilitate practical help.

The objectives of Pathways to Peace include among others to facilitate safe spaces for honest exchange between Ukrainian and Russian church leaders, to develop a network of church leaders and other civil society leaders for exchange on the preparation of peace or to bring together European youth, in particular Ukrainian and Russian young refugees.

The immense potential of faith actors in transforming conflict and building sustainable peace seems to have gone largely unnoticed in the public sphere. Given the prominence of faith in this conflict, it is about time that all relevant actors in our societies, including faith-based initiatives, joined forces to counter this major crisis of our time.

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America

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Trauma

12 September 2025

3 min read

Why Charlie Kirk’s murder shook me so much

When violence hits close to home, we search for answers

Will Fagan

Will Fagan serves as a minister in the Episcopal Church in Birmingham, Alabama.

Mourning students at a vigil hold a sign about Charlie Kirk.

Students at Texas Tech hold a vigil for Charlie Kirk.

X.com/OldRowOfficial.

Unless you've managed to avoid all news this week, you’ll have heard of a series of unconnected violent attacks in the United States, the most recent being the assassination of 31-year-old conservative political activist Charlie Kirk during a speaking engagement at a university in Utah.

Every time there is a shooting in my country – whatever the motives – I become physically sick and had a similar reaction this week. I cannot watch the news; I delete social media and avoid the topic in conversation as much as possible. Our present and public culture of violence coupled with the resultant news cycle is simply too much, too fear-inducing, and leaves one with the helpless thought of, “what would happen if I was in a situation like this?” I’m sure I’m not alone in this response.

I do not agree with Kirk’s politics (though as an ordained minister, I wouldn’t tell you if I did), yet what I can tell you is that his death has gripped me in a way I couldn’t have foreseen, nor expected, becoming strikingly close to home. Kirk was 31 with a three- and one-year-old child. I am 32 with a three- and one-year-old. The idea that this could happen, period, followed by the thought of a prospect of never seeing my own children grow up completely undoes me.

This is undoubtedly a common response to when tragedy strikes individuals with whom we can readily identify. I doubt I have to list examples (were you 37 years old when Princess Diana died?; etc). because you’re probably thinking of certain instances right now in times where tragedy has hit, even metaphorically, quite close to home.

As I write this not from a gun control perspective, nor a political one at all, what is the theological answer to why events like this continue to happen? It is a question that I have been asked, unprovoked, by three young fathers (of diverse political persuasion) this week who have been gripped similarly to me.

What continues to come to mind is a blanket statement written by the Apostle Paul in his first century letter to the Galatian churches in which he calls the backdrop of our lives, “This present evil age.” It is a harsh statement, and it is unpleasant, but I also think it is true. How, you ask, can I apply this first century statement to 21st century life?

For one, Paul is writing about the time before Jesus Christ returns, a time that Christian teaching states that we presently occupy, so the statement does apply. But perhaps more importantly, when I look around, I confess that, especially in weeks like this one, “this present evil age” is an existence that I recognize. It is an existence that tragically we can largely expect, an existence that cannot be fixed politically, personally, or corporately as much as we would like to.

Rather than depressingly stripping us of agency, how is this helpful? I find it helpful in two key ways: First, this present evil age as a descriptor is helpful because it helps answer, “Why?” to my despondency, confusion, and nausea at senseless tragedy. It helps me put those feelings somewhere and begins to, if only slightly, give the nonsensical a name.

More than that, though, it forces me to look beyond this world, and to a power greater than the seen forces here – a power that I cannot see, a power that is good, merciful, and just, a power that will one day, and hopefully soon, make all things new.

Of course, we cannot make sense of senseless and violent and sickening tragedy. We weren’t meant to, and that is grievous. So might we only call on the name of the one who has come to this present evil age before, and that he might come again – soon.

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