International Humanitarian Law
The Rules That Exist Inside Wars — and Why They Aren't Naive
The idea that war has rules sounds absurd until you realise those rules are the only thing standing between a battlefield and a massacre.
The Idea
International humanitarian law — often called the laws of war, or IHL — is one of the most misunderstood bodies of law in existence. The common objection is obvious: if people are already killing each other, why would they follow legal norms? The objection sounds clever, but it mistakes the purpose of IHL. It was never designed to stop wars. It was designed to limit their brutality once they start. The Geneva Conventions, most recently updated in 1949 with additional protocols added in 1977, form the backbone of IHL. They distinguish between combatants and civilians, protect prisoners of war from torture and humiliation, and prohibit weapons that cause unnecessary suffering. These aren't aspirational principles — they're binding treaty obligations on nearly every state on earth. The deeper logic is reciprocity. Armies largely follow the rules not out of moral conviction alone, but because their own soldiers might one day be captured, and they want the other side to have an incentive to treat them well. This is law functioning as a kind of mutual insurance policy. What makes IHL genuinely fascinating — and genuinely difficult — is the concept of proportionality. Killing civilians is not automatically a war crime under IHL. If a military target is significant enough, civilian casualties may be legally permissible, as long as they are not 'excessive' relative to the anticipated military advantage. Who decides what counts as excessive? Largely, the attacker. This is where the law's idealism meets its hardest edge.
In the World
On 8 May 1828, a Swiss businessman named Henry Dunant was travelling through northern Italy when he stumbled across the aftermath of the Battle of Solferino — one of the bloodiest engagements of the 19th century. Around 40,000 soldiers lay dead or wounded across the fields, and there was almost no organised medical care for any of them. Dunant, who had no medical training and no official role, spent three days coordinating local volunteers to tend to the wounded from both sides. The experience broke something open in him. He wrote a short book about what he had witnessed, called A Memory of Solferino, and proposed two ideas that seemed radical at the time: that every country should have a voluntary relief organisation trained to assist the wounded in wartime, and that an international agreement should protect medical personnel from attack. Both ideas were adopted. The first produced the Red Cross movement. The second produced the First Geneva Convention of 1864. Dunant's insight was not that war was wrong — he took no position on that. His insight was that suffering which serves no military purpose is pure waste, and that even enemies can agree to reduce it, because both sides benefit. He was awarded the first ever Nobel Peace Prize in 1901, though by then he had spent years in poverty, having been financially ruined and effectively erased from the movement he founded by a colleague who resented his influence. The rules he helped write outlasted every indignity done to him.
Why It Matters
Most people encounter IHL only when a conflict is in the news and someone accuses someone else of a war crime. At that point it tends to feel like a political football — invoked selectively, enforced inconsistently, and dismissed by the powerful. That cynicism is understandable, but it misses something important. IHL represents one of the few areas in human history where the world collectively agreed that even in extremity, some things are off-limits. The fact that the rules are broken does not make them meaningless — every legal system is broken sometimes. What matters is whether the norm exists at all, because norms shape behaviour at the margins even when they don't determine it absolutely. Knowing this changes how you read conflict reporting. When a journalist describes a hospital being struck, or prisoners being paraded on camera, they are describing not just a horror but a legal event — one with defined obligations, potential accountability, and a body of jurisprudence behind it. The International Criminal Court exists, in part, because of the architecture Dunant helped imagine. Imperfect, contested, underfunded — but there.
A Question to Ponder
If a rule cannot be reliably enforced, does it still do meaningful work in the world — and how would you know?
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