"To destroy a library is to erase part of the cultural memory of humankind": Margaret MacMillan on war

For too long we’ve wanted to avert our eyes from war, viewing it as something distasteful. But we don’t do ourselves any service by that. We need to understand war. I don’t think we have any hope of stopping it, in fact, unless we understand more about it.

How has war impacted on societies throughout history?

Big, demanding, expensive wars have tended to compress the poles of society. In fact, there are those who argue that the greatest times of social equality have been in the face of great catastrophes. Both wages and rates of taxation generally go up in war, which means that those who have a lot give a lot, while those who are at the bottom often come out better. You saw this in the 20th century – taxes went up, largely because of the need to fight wars, and never quite went back to normal. Governments discovered that they could squeeze far more wealth out of societies than they had suspected. And once governments know that, it’s very hard to go back.

Wars have often benefited certain sections of society who were not well-treated beforehand. It was only after the First World War, for example, that some British women got the vote. That’s a change that wouldn’t have happened as quickly otherwise. The government recognised that it had depended on women to sustain the war effort. They simply couldn’t deny them the vote any longer.

In more extreme instances, war has led to revolution. Russia’s story would have played out very differently without the First World War. I don’t think the Bolsheviks, who were a tiny little factional party at the time, could have taken power without it. That, of course, changed not only Russian history but also the history of the modern world.

And conflict has influenced our cultures in more subtle ways that we might not even notice. There is still a sort of fascination and glamour that surrounds war. Bookshops are crammed with war stories, and it’s the subject of many video games and films. But I think the less you really know about war, the easier it is to be beguiled by it. That can be dangerous, because unless we understand how awful war is, we’re inclined to take it lightly and underestimate the risks.

Another way that war can enact change is through supercharging technology and science. Can you give some examples?

Yes, things happen in wars which don’t seem likely or even possible in peacetime, often because they’re simply too expensive. But when it’s a matter of survival, suddenly the question of expense becomes less important. The classic example is penicillin. Its ability to cure hitherto incurable diseases was discovered in the 1920s and 1930s, but it was too expensive to put into production. Along comes the Second World War, and the need to keep soldiers alive on battlefields. The ability to produce penicillin on an industrial scale that resulted from the war had an enormous and long-lasting impact on public health across the world. That just shows how the pressure of necessity speeds up innovation. It’s a terribly costly way of making advances, but one of the paradoxes of war is that it does often produce social, technological and scientific change that can benefit people in peacetime.

What determines whether a society valorises or condemns war?

Who is in charge always matters. In the Middle Ages, those in command tended to be those with the resources for military equipment, who dominated their societies through sheer brute force. But war was very expensive. If you wanted to equip a knight in armour, you needed a lot of resources. You also didn’t want ordinary farmers fighting, because they were much more valuable producing food. That meant that military virtues were confined to a small, elite class.

Cultural values also matter a lot. In 18th and 19th-century Prussia, for example, the most honourable career of all for the upper classes was the military. Young people were brought up to be brave, to accept discipline and be willing to sacrifice their lives – the sort of values that produce combatants. Of course, in other types of societies, people who are prepared to accept military discipline are regarded as not having much imagination or independent spirit.

The particular kinds of wars that societies fight always reflect their own values. For example, democracies fight wars in different ways to authoritarian societies, partly because they have different value structures. In authoritarian societies, it’s easier for governments to make people fight. If you grew up expecting to die bravely on the battlefield, then you are already predisposed to fight, unlike in a democracy where we’re taught every individual life ought to be valued. This means that democracies can only fight successful wars with public support. The two world wars had a tremendous amount of popular support in the Allied democracies, as people felt that they were ‘just’. But democracies that fight unpopular wars end up usually not doing very well. Both the French and the United States had to pull out of Indochina because the wars they fought there were deeply unpopular, and they simply weren’t able to sustain them.

You argue that while there are endless excuses for the beginnings of wars, there are just a few underlying causes for war. What have they been?

You can basically boil down why people go to war into three reasons. Firstly, people go to war out of fear. They need to defend themselves. They feel that those they love and their way of life is under attack. Secondly, people go to war because of greed. They want some of what someone else has – a piece of land, loot, or civilians to turn into slaves. The third reason people go to war is over ideas. People will fight and die for things like their nation, revolution or religion.

While these basic motivations have come up time and time again, the means and methods of war have evolved beyond recognition. What are some of the transformational turning points?

The recurring pattern is that an innovative technology will come along, which precedes a successful new style of fighting. For example, when horses began to appear, it suddenly produced warriors who were much more mobile. For a time, warriors riding horses or driving chariots really carried all before them. When you think of the enormous empire-building power of the Mongols, that was largely down to the skill of warriors on horses to overwhelm troops on the ground.

Gunpowder was another such innovation. If you look at medieval castles, they have these lovely tall walls. But once you got heavy-duty cannon, those walls became a lot less of a protection. By the time you get to the 17th and 18th centuries, castles were much squatter and the walls much thicker, so they wouldn’t be demolished by cannonballs.

Industrial nations developed an enormous capacity to produce consumer goods. But along with that, they gained the capacity to kill on literally an industrial scale

In the modern era, a technological advance that made a huge difference was the internal combustion engine. When Napoleon marched his army into Russia in 1812, his force was probably about 600,000 strong. What really destroyed that army was hunger and cold, because there was no way to supply that number of troops. But by the 1870s, that would no longer have been the case. With the emergence of the railway it became possible to move enormous numbers of troops and crucially, keep them supplied. That meant you could keep them in the field much longer. There are always innovations, but sometimes it takes a while for us to catch up and learn how to use them.

What do you see as the hallmarks of war in the modern era?

War changed hugely in the 19th century, partly as a result of the industrial revolution, and partly also as a result of the growth of mass society, when people participated in public life and the affairs of their government. Given the massive increase in the scale of war in the 19th century, I sometimes think that perhaps people shouldn’t have been surprised when the First World War came, with its huge number of combatants.

In the 19th and 20th centuries, industrial nations developed an enormous capacity to produce consumer goods, which made life better for lots of people. But along with that, they gained the capacity to kill people on literally an industrial scale. Once you got automation, standardised parts and assembly lines, it became possible to produce an awful lot more equipment. This wasn’t just guns. It was boots, caps, shoes – anything and everything that a body of men might need. You can have all sorts of brave people, but if they don’t have boots or food, even the bravest people can’t fight for long.

Something else that really came into focus in the 19th century is that people began to feel a passionate attachment to something called ‘the nation’. People were prepared to fight and die for this abstraction, which resulted in the motivation to fight bigger wars.

All of this led to the emergence of what we would call ‘total war’. That means mobilising all a society’s resources – brains, capacities, money, materials – for the purpose of waging war. But it’s also about what you’re willing to do to the other side. You’re no longer just going after those who are fighting. You’re going after the entire social, economic and political structure supporting them. Increasingly, we see attacks on civilians, and attempts to weaken morale and undermine the confidence of people in their own governments. Total war really becomes a question of society against society.

How have ideas about the acceptable boundaries of conflict changed over time?

It may seem futile, but throughout history we’ve made attempts to limit war and indeed outlaw it. The ancient Greeks had rules about when one side would concede, rather like a sporting match. The medieval church was always trying to say, “no, you mustn’t attack priests”, and bring in rules against fighting on holy days. Now we have the Geneva Conventions to dictate how civilians should be treated. But although there is a body of law in existence, we often ignore it.

I think that shifting boundaries of war are probably more about changing means than changing morality. You can look back at the past and find countless attacks on civilians. In the Middle Ages, for example, there was a technique called chevauchée, where if you couldn’t get at a leader holed up in his castle, instead you would devastate the surrounding countryside, killing his workers and farmers as a way of forcing him to surrender. Attacking civilians has a very long history. But in the 20th century it became possible to get at the other society in ways that hadn’t been possible before. The means of actually disrupting enemy societies became so much greater.

Has humanity become more or less violent?

That’s a huge debate. Steven Pinker and others have argued that we’re becoming a gentler people, seen in the fact that there’s less domestic violence and animal cruelty in many countries. But I think that organised violence – or war – is something different.

On the surface of it, a lot of western societies are no longer militaristic in the ways they once were. Sweden, for example, was highly militarised in the 17th and 18th centuries. If you heard the Swedes were coming, you got out of town because they were known as ferocious soldiers. Of course, it’s very different now.

We like to think that we’ve enjoyed a long period of peace in the west since 1945, but perhaps we have not looked closely enough. The Troubles in Northern Ireland only ended in 1998. And what happened in Yugoslavia in the 1990s can’t be classed as part of any ‘long peace’. Then, what about the rest of the world? In a sense, western countries have just exported war elsewhere. The French and the US in Indochina, for example, funded groups to prolong wars in another part of the world. We’ve also witnessed, even in supposedly peaceful countries, prolonged civil unrest with a lot of violence. Latin America, for instance, has not seen a major state-to-state war for a very long time, but it’s had an awful lot of violent internal conflict. And so I don’t think we should see this period as free from violence. Certain societies have just been fortunate enough not to experience it at home.

What do you foresee as the future of conflict?

Predicting the future is always a tricky business, but what I suspect we’re going to see is the growth of very high-tech war – war that’s increasingly automated and relies on artificial intelligence. We’re already seeing war moving into space, in spite of international treaties, and war moving into the cyber world.

But I also suspect what we may see at the other end of the scale is continuing low-level wars that rumble on, overlooked by the rest of the world: around the Great Lakes in Africa, in Afghanistan, in Syria and other parts of the Middle East. They will not be high-tech wars, by and large, but as we’ve seen, you don’t need high-tech weapons to kill large numbers of other people. A lot of the killings in Rwanda were done with machetes and hoes.

So you think that war will continue to be an intrinsic part of human history?

The fact that there will be war in the future, I think is almost certain. There are still those who see war as a tool for getting what they want. Political leaders are still prepared to contemplate war to achieve their own ends. You certainly see that with the various warlords engaged in conflict in places such as Afghanistan. I do worry about nuclear proliferation, which I predict will happen. Nuclear weapons are now much stronger, easier to deliver and simpler to acquire than they were during the Cold War.

We need to think really seriously about these things, because the capacity of war to destroy humanity and the planet is much greater than it was even 10 years ago.

War: How Conflict Shaped Us by Margaret MacMillan is published by Profile and is out now.

Listen to an extended version of this interview with Margaret MacMillan on our podcast

This article was first published in the December 2020 edition of BBC History Magazine