Three years ago, I killed several thousand people over the course of a single weekend. Late into the night, I ran around butchering everyone I saw, until by the end I didn’t even feel anything any more. Just methodically powering through it all, through the wet sounds of splattering heads, bodies crumpling, shiny slicks of blood. I thought I was past caring. But when I finally went to bed, I couldn’t sleep, and in my dreams I was haunted by all the men I’d killed. I saw their brains exploding, again and again and again.

In my defence, I’d had a bad week. It was December: a grotty English winter, not particularly cold but still utterly grim. The kind of winter that seems to stick to everything, like a layer of congealed grease. I was worried about money. My political party had just been utterly humiliated in a general election. I was feeling down. So I cancelled all my plans that weekend and decided to spend two days playing video games.

This isn’t something I usually do: the last time I’d devoted this many waking hours to gaming was as a student, when I’d smoke too much weed and forget which knob on the controller was which, with the result that my character would walk around snapping his head up and down in an alarming and nausea-inducing fashion, firing in random panic, usually at my own team mates, until I either wandered obliviously off a cliff or someone got bored of the whole sad spectacle and grabbed the controller out my hands. I am not good at these things, which is why I generally avoid them. But my flatmate had a PS4 and there was nothing I wanted to do except wallow in my own misery for a while, so I did.

It was a war game. Not all of them are: the best-selling video game in history, Minecraft, is a kind of digital Lego. Players have built Aztec temples and Mesopotamian cities; the Danish government once commissioned a 1:1 scale replica of the entire country. Games like Tetris and Pac-Man have still outsold just about every shooter on the market. Still, war keeps cropping up. The last instalment in the Call of Duty series – in which players kill various enemies of US foreign policy to advance the cause of freedom – sold 30 million copies. PUBG: Battlegrounds – in which players kill each other for no apparent reason at all – sold 75 million copies. With the technology available, we can imagine ourselves doing anything. But again and again, we do this.

I think these games do something deeply unpleasant to our brains. I’m not even talking about the violence; it’s more fundamental than that. When you’re playing a first-person shooter, the game takes over your entire visual field, along with your entire sense of space. Other games don’t do this – if you’re pretending to be the owner of a sports team, or a duke commanding medieval armies, or if you’re solving little puzzles, it’s always through some kind of interface. But shooters replicate the sense of being in a world.

The more terrorists I killed, the more every-thing beyond the edges of the screen started to darken and blur. I was barely conscious of the sofa I was sitting on, or my own body. Eventually I realised it was dark outside, and I’d gone an entire day without eating. I didn’t feel particularly hungry, but I managed to tear myself away from the screen and go to the supermarket anyway. I walked in a kind of trance; the outside world felt flat and paper-thin, loud in all the wrong ways, and somehow less real than what had been happening on screen. People walked past on the high street, brisk in their winter coats, and I thought about pulling out a gun and popping their heads open. It was all I knew to do.

Marshall McLuhan described electronic media as a form of ‘desperate and suicidal autoamputation’. The medium locks off our human senses, detaches them from the body and turns them into the object of a numb fascination. ‘Such amplification is bearable by the nervous system only through numbness or blocking of perception.’ He was writing in 1964, eight years before Pong; a modern first-person shooter can amputate your senses in ways he could have barely imagined. My weekend of simulated violence was probably the most messed up I’ve been since I stopped taking cocaine. I didn’t just feel numb: I felt drugged.

Armies have a habit of drugging their soldiers. In just four months in 1940, Nazi Germany delivered some 35 million tablets of Pervitin – what we would now call crystal meth – to its soldiers. Britain similarly dosed up its conscripts with Benzedrine; the Soviets used a particularly nasty compound called Dinitrophenol, which kept the heart rate up and reduced the sensation of cold, but also happened to be a high explosive. Today, the US armed forces hand out ‘go pills’ by the fistful. Syrian militias fuel themselves on cheap speed. Vietnam veterans have described the experience of heavy combat on a mind-bending quantity of Dexedrine: ‘Every sight and sound was heightened. You were wired into it all.’ Hyper-focused and woozy, stuck in the pulsing nausea of it all. Each sensation is intense, but you are not quite there: like looking at the world through a screen. Hence the bravado, the recklessness, and the massacres.

I know that feeling, and you can get there without any drugs. There are a lot of aspects of war that no video game will ever be able to capture, but this is not one of them. The games don’t just realistically simulate war; somehow, they partake of the same thing.

Real war is certainly starting to take cues from the simulation. Fighters wear GoPro cameras on their helmets and upload the footage to the internet; you can watch actual combat from the same jerky first-person perspective as any gamer stream on Twitch. When the American military needed a control system for its fleet of armed drones, they opted for the Xbox controller. In 1991, Jean Baudrillard could write that the Gulf War was not really taking place, and whatever was taking place was doing so on the terrain of the CNN nightly news. ‘The media promote the war, the war promotes the media, and advertising competes with the war… War, when it has been turned into information, ceases to be a realistic war and becomes a virtual war.’ Today, war is not TV, but pure interactivity: Ukrainian soldiers adjust the path of their Stugna-P rocket on one screen, you watch the footage of them doing so on another, and for a moment you’re in the same digitally mediated nowhere as the war itself.

Maybe war has always been a kind of game – for some. The Aztecs had their ‘flower wars’, pitched somewhere uncomfortable between what we would recognise as actual war and a kind of deadly ritualised sport. Every year, at an agreed place on an agreed date, they would face off against the armies of Tlaxcala or Cholula. Soldiers would forgo the use of darts or throwing-spears; the point wasn’t to wipe out the enemy forces but to perform feats of hand-to-hand combat and bring home captives for sacrifice. When the Spaniards arrived, they shocked the Mexica by not following the rules of ritual warfare, but there are parallels in European history too. For the chivalric classes, late-medieval warfare was also a sport, or a kind of art, a delicate refinement of the self.

At the Battle of Crécy, near the start of the Hundred Years’ War, one of the dead was King John of Bohemia, who had joined on the French side mostly out of love for the thrill and honour of knightly combat – despite his also having been blind for ten years. Later in the same war, Jean de Bueil would describe the conflict that had ravaged his country and killed off a good portion of its ruling class in tones of rapture. ‘It is a joyous thing, is war… There arises such a delectation, that he who has not tasted it is not fit to say what a delight it is.’ All the other noble games – jousting, tournaments, even chess – faded next to the greatest game of all.

Most gamers today do not want to fight in an actual war. When Vladimir Putin announced mass mobilisation for the war in Ukraine last month, one of the effects was a sudden and massive dip in the number of people playing the enduringly popular 2012 shooter Counter-Strike: Global Offensive online. The game is particularly popular in Russia, which accounts for over a tenth of its player base; now, many of those young men are busy trying to flee the country.

But elsewhere, militaries seem to sense that these games are not a substitute for their own activities, but part of the same thing. The US military released its own game, America’s Army, in 2002; it has also sponsored Call of Duty tournaments. They’re not the only ones. Hezbollah has produced a series of video games: in 2003’s Special Force you fight off invading Israelis; in 2018’s Holy Defence you’re battling against Isis.

War Games, the blockbuster new exhibition at the Imperial War Museum London, is in a bit of a tricky position. On the one hand, the museum’s general stance is that war is bad, a view I broadly endorse. Which means that turning war into a cheap interactive Tuesday-night entertainment is something that we should, at the very least, want to think carefully about. At the same time, though, the museum is clearly courting some of the 62 per cent of the country who play video games (it includes a ‘retro game zone’ where you can shoot at things on an Atari 2600 or Sega Dreamcast), and the exhibition is sponsored by Rebellion, the studio behind the recently released Sniper Elite 5.

Some space is given over to more interesting indie games, in which you explore the journey of a Syrian refugee through WhatsApp messages or try to build a civilian resistance to Nazi Germany. There are heartbreaking objects, like the Yamaha keyboard left behind by a Mosul resident as he fled Isis forces in 2014. But there’s also an entire room devoted to Call of Duty and its hyper-realistic physics, where the sound of a gunshot travels at the actual real-world speed of sound, and there’s a delay if someone fires a shot on the other side of the map, so you’ll never hear the bullet that kills you. Isn’t that cool?

I am not saying that people should be deprived of their fun. But I am questioning how fun this stuff really is. The IWM has roped in various psychologists and gamers to talk about why it is that people play these things so much, and the consensus is that games offer a kind of freedom: unlike with a book or film, you can move around at will, you can make decisions, you are an active participant and not just an observer. Games allow you to do things that wouldn’t be possible in ordinary life, like killing without consequences. But I wonder – is this really true?

The anthropologist David Graeber made an important distinction between games and play. In pure play, you really are actively engaged; the world is unbounded and anything is possible. ‘Play can be said to be present when the free expression of creative energies becomes an end in itself.’ In games there are rules. A chess piece can move in one particular way only. Your character in a war game can only run and aim and shoot.

When I’ve given up hours on end to video games, it didn’t leave me with any real sense of freedom. It felt like the game and its logic were swallowing up my entire consciousness, until simply navigating the real world became a terrifying ordeal. Gamers have started to complain that the blockbuster titles have become strangely joyless, addictive but empty: so many of them are basically elaborate Skinner Boxes, rewarding you for mindless and repetitive tasks. They feel trapped by their own entertainment. But a non-aristocratic soldier in a real war lives through the same thing: he has to do exactly as he’s told, to kill on orders, and to die if his country demands it. Maybe this, and not freedom, is what gamers are really looking for. To go limp and numb and thoughtless: to surrender.