A painting of phantom horsemen on the battlefield

Can we really have ‘rules’ of war?

We hear a lot about the rules of war. The conventions that dictate what is acceptable behaviour in conflict situations and what is not. But what are these rules? How are they defined? And can we really have such a thing as ‘rules’ of war in today’s troubled world?

It’s a matter of debate whether war is a fundamental and inevitable aspect of human nature or the result of specific economic, social or other circumstances. What is certain, though, is that the notion of war has been around for pretty much as long as we have. And it doesn’t look like it’s going anywhere soon.

We generally regard war as an intense and sustained armed conflict between governments, states or nations. But it can apply equally between different groups within a country. Or, indeed, between a state and a non-state group, such as a paramilitary organisation.

Such is the ugliness of war that those waging it have long sought legitimacy for their actions. This has given us the idea of a ‘just’ war. A set of criteria establishing when and how a war can rightfully be fought. A suite of moral standards as to what is acceptable in war and what is not.

This doctrine of ‘just’ war has three parts. Jus ad bellum addresses the right to go to war. Jus in bello considers how war is fought. And the emerging jus post bellum deals with what happens after a war has been fought.

In order for a government, state, nation or other entity to be justified in starting a war, jus ad bellum dictates that it must have appropriate political authority within a system that recognises and espouses the principles of justice. It must also have just cause to go to war, have exhausted all non-violent options and have a realistic expectation that its aims in starting the war can be achieved.

Once a war is being waged, jus in bello demands that acts of war should be directed at enemy combatants, not at non-combatants or civilians. Military actions should be limited to those that are necessary to defeat the enemy and harm caused to civilians or civilian property should be proportional to the military advantage gained.

Jus in bello also requires that prisoners of war are treated fairly and that methods of warfare that are considered ‘evil’, such as mass rape and the use of biological weapons, are avoided.

The idea of a set of rules for what should happen after a war has concluded is a more recent addition to just war doctrine. The principles of jus post bellum include that the rights and traditions of the defeated party should be respected, that no punishment should be imposed on the innocent or on non-combatants, and that claims for compensation or reparations should be reasonable.

Jus post bellum also wrestles with the thorny question of the extent to which a defending party can pursue aggressors even after the immediate threat has been neutralised and the war has ceased.

There are, of course, those who argue that no war can ever be just. That all disputes can and should be resolved peacefully and without resort to physical violence. But there are, equally, those who argue that if you need to fight to defend yourself or to prevent a greater evil, then you really shouldn’t feel guilty about it.

The idea of just war has a long history. Aristotle proposed that we should fight wars as a last resort and in a way that allows for the restoration of peace. St. Augustine recognised that we may, on occasion, need to use violence to prevent a greater wrong. And it was St. Thomas Aquinas who brought together the various currents of thought to established the first principles – in the western world, at least – of what makes a just war.

Just war is not, however, a purely theoretical notion. It now forms a fundamental part of western military ethics. And it provides the foundation for much of international humanitarian law, notably the Geneva Conventions.

However, the principles of just war have come under scrutiny in modern times, following the advent of nuclear weapons and conflicts such as the Vietnam war. Indeed, some thinkers – such as philosopher Michael Waltzer – argue that the circumstances in which wars are fought has changed so substantially that we really need to rip up just war doctrine and start again from scratch.

While I don’t have a problem with the just war doctrine as such, though I’d prefer it if we could resolve our differences without recourse to violence, I do worry about its ongoing fitness for purpose in the modern world.

For a start, the just war doctrine – and, indeed, our definition of war itself – focuses on actions taken by governments and other state actors. But armed conflicts in today’s world increasingly involve non-state actors, such as criminal gangs and terrorist groups. How do we apply the principles of just war in such circumstances? And how do we respond when the lines between state and non-state actors become blurred?

Furthermore, the implicit assumption underlying just war theory is that by fighting a war ‘cleanly’ and with honour, we can contain it and stop it from escalating. But does this assumption continue to hold in a world that is as politically, economically and socially interconnected as the one in which we live today? And what about when we move beyond the notions of rational military aims and proportional response into the all-encompassing – and perhaps somewhat less rational – worlds of totalitarianism and religious fanaticism?

Moreover, like any system of rules, the just war doctrine requires universality. We all need to be playing by the same rules. But our ideas as to what is appropriate in a wartime scenario are, in many cases, culturally specific. And some people just don’t care for rules. Are we binding our hands unnecessarily if we seek to maintain our honour against a foe that has a different conception of honour? Or that has no conception of honour at all?

Finally, is it always reasonable to expect those engaged in combat – whether states or individuals – to act proportionally and with restraint? Or not to seek revenge? G. K. Chesterton wrote that “the true soldier fights not because he hates what is in front of him, but because he loves what is behind him.” Would we not throw our moral principles to the wind and use all means at our disposal if we and those we love faced annihilation?

Don’t get me wrong. As long as war is a feature of human existence, I’d like us to have rules for its conduct. But they need to be the right rules. And they need to work. Things have changed considerably since the time of Aristotle and St. Thomas Aquinas. Our thinking about when and how we can legitimately wage warfare, as well as about what we do afterwards, needs to catch up.

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Image: Birmingham Museums Trust on Unsplash






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