John Green:
     Hi, I'm John Green, this is Crash Course World History, and today we're gonna respond to your many requests and talk about a controversial subject: war.
     So here at Crash Course, we're really not that into the history of war, partly because we feel it's been discussed well elsewhere and partly because we haven't really figured out a way to tackle it.
John from the Past:
     Mr. Green! Mr. Green! No no no no no, that's all history is. It's a series of wars.
John Green:
     Well, Me-from-the-Past, I can certainly see why you would think that, because that's how many history classes are organized, but in fact, I don't think that history is primarily about war. 
     But, I mean, humans find all kinds of ways to die- like, you could teach a whole Crash Course World History on smallpox. In fact, we kind of did that last week.
     Ultimately, I find cooperation and trade more interesting than the violent and destructive aspects of world history because I think they probably ultimately matter more, but I do have to admit that war is a pretty big deal in world history, so we'd better spend some time talking about it, at least in the abstract.
[Crash Course World History II Intro]
     So today we're gonna focus on the question of why people fight and, more specifically, why human beings go to war. Like, to put it another way, we're gonna look at whether making war is part of, quote, "human nature."
     This gets into some nit-picky, how-many-angels-can-you-fit-on-the-head-of-a-pin questions about nature, but we're just gonna put those aside for now.
     So, are human beings hard-wired to fight and kill each other? Well, that's a question that philosophers have been asking for a long time. Like, Nietzsche summed it up this way:
     "I am by nature warlike; to attack is among my instincts."
     But he was Nietzsche. He had a number of instincts that I'm pretty sure were not universal.
     Anyway, that attitude might explain why Nietzsche is so popular among the group most likely to go to war: young men.
     Now, among slightly less scary philosopher[s], the question of humans' warlike nature is often described as a debate between Hobbes, who saw humans as warlike and violent, and Rousseau, who thought that humanity was naturally peaceful until civilization came along. And we've heard echoes of this debate throughout our study of world history. Like, were we better off as foragers, when we had way more time for skoodilypooping? Stupid civilization, always ruining everything. Let's go to the Thought Bubble.
    So, was Hobbes, right that life in the so-called "state of nature" was nasty, brutish, and short, or was Rousseau right, that it was amazing? Well, without a time machine, which would settle a lot of vexing historical questions and would also allow me to go back and fix my terrible, terrible mistakes at the eighth grade cotillion, our best guide to what people were like in the old state of nature comes from anthropology.
     Making guesses about the very distant past based on observations of modern hunter-gatherers is extremely problematic, but it's the best we have to go on. Well, that and archaeology.
     So, what do anthropologists tell us? Well, it doesn't look so good for Rousseau. Many anthropologists suggest that, in pre-civilization social orders, things were pretty violent. In Australia, for example, killing and fighting was among the main causes of mortality, and archaeology has revealed evidence of warfare going back thousands of years. Now, some of these anthropological conclusions are controversial, but when combined with cave paintings and fossils of humans who pretty obviously were killed by other humans, it seems clear that we've been killing each other for what historians like to call a "long-ass-time."
     So Hobbes seems to be right, that life in the state of nature was probably violent and brief, but was it war? Again, anthropologists can give us some guidance here. Some studies have reported relatively large-scale brute confrontations similar to battles, but these tend to be largely symbolic and they often don't result in much killing. Most of the actual violence that hunter-gatherers commit against each other takes place during raids, in which one group sneaks up upon another and attacks.
      So in the end, there may be, like, a very violent middle path between the individual killings in, like, Cain v. Abel, and the modern wars that we see today.
     But why are we seemingly so hard-wired toward violence? Well, it might be evolution.
     Thanks, Thought Bubble. So I wanna be really clear about something. Uh, we may have aggression "in our genes," but you can't kill people!
     And also, you don't have to. Many of us, most of us, in fact, make it all the way through life without killing a single person. So I think it's going too far to say that our genes have, like, made us into stone-cold killers, but it is possible that aggression is an innate trait in humans, and under the right conditions, maybe it finds its expression in violence and war.
     Now, we should all be very skeptical about applying evolutionary biology to cultural characteristics, like warlike behavior, because Darwin's ideas have been misused to explain all sorts of unpleasant things, especially in 19th-century concepts about race.
     You know, if you're in a structurally privileged position in the social order, it's easy enough to be like, "Huh. I wonder how I got here. Probably natural selection." when in fact, slavery was not a function of biology. It was a function of oppression.
     And another reason we should be wary is that we often refer to cultures "evolving" very quickly, often in a generation, but biological evolution takes a lot longer.
     That said, there are a few ways that evolutionary imperatives could contribute to a warlike human nature. We'll start with the idea that it is a biological imperative to pass on genetic traits to successive generations.
   Because our close relatives and kin contain the most genetic material in common we naturally want to protect them and ensure the continued survival of our genes; so we might be expected to fight in order to protect members of our kin group. But then again, trying to protect your family from harm is somewhat different from killing other people's families.  
   Well here's where it's helpful to remember that for the vast majority of human history, war consisted of raiding. It was about taking stuff from other people's kin groups so that your kin group could have that stuff. For 99% of human history that's how we fought, not as organized states warring with each other.
   So let's stop even thinking about, like, groups of humans, or even individual humans, and think for a second about genes. Insofar as genes want anything they want to go on; life wishes to continue. And for those human genes to go on they needed humans to go on, and for that we need two resources: food and sex. Both of which could be quite scarce in the many millennia before we settled down into agricultural based societies.
   It also occurs to me they are also quite scarce in most American high schools, unless you consider Cheetos food.
   So you can easily see how the competition for these two resources could become violent, and might provide an evolutionary explanation for war. Like skill and fighting meant more access to food in the form of better hunting grounds. It also meant more food because you were better at fighting the food too.
   And there's a more horrifying aspect to this as well, which is that in many of these raids women were the principle goal: they were to be acquired. Also, as we know from the Odyssey, fighting has a tendency to breed more fighting. Like, you kill my friend it makes it more likely that I'm going to kill you.
   I'm not going to kill you, but seriously don't kill any of my friends.
   We see a bit of this phenomenon in a description of inter-tribal warfare among North American plains Indians:
   "In an atmosphere charged with inter-tribal distrust even an imagined slight by an outsider could lead to retaliation against other members of his tribe... it was much easier to start a war than to end one"
   And as you may have noticed, that's still true today.
   But okay, if war was a response to scarce resources why do we have wars now - resources are relatively easy to acquire?
   Well that's a complicated question and we're gonna talk next week about how war may actually have contributed to civilization and proven socially useful by helping us create kingdoms and states. 
   But another way to examine the question of why we fight is to examine what soldiers have said about why they fight. 
   So here's one such voice (although I wanna be clear that there are millions of them). Karl Marlantes was a marine lieutenant in Vietnam who wrote about his experience in the novel 'Matterhorn' and a memoir called 'What it is like to go to war'. That book includes a number of uncomfortable revelations about the way soldiers often think and feel about war.
   For one thing, Marlantes tells us that soldiers achieve a sense of transcendence through fighting by becoming part of something bigger than themselves. Also he says:
   "There is a deep savage joy in destruction, a joy that goes beyond ego enhancement."
   Now today's soldiers rarely fight for food or mates, but they do fight for each other. And not wanting to let your comrades down, feeling loyal to the group - those are powerful motivators.
   More viscerally, fighting is exciting to humans. It gets the adrenaline pumping. According to Marlantes "combat is the crack cocaine of all excitement highs." (Neither of those things sound at all fun to me but I guess we're all wired differently).
   So what do we do with the fact that for many of us there is joy and power in killing? How do we respond when a former pilot tells us, as he whispered to Marlantes, that he enjoyed Napalming the enemy? Saying "I loved it, I lit up the entire valley". How do we respond to Marlantes' revelation that during Vietnam he "ran toward the fighting with the same excitement, trembling and thrill as a lover rushing to the beloved."? 
   Well I think Marlantes reminds us that despite our biology, soldiers, just like the rest of us, have free will: they make choices.
   Marlantes also notes: "choosing sides is the fundamental first choice that a warrior makes... the second fundamental choice of the warrior is to be willing to use violence to protect someone against intended or implied violence.". 
   Now for many humans over millennia that choice hasn't been much of a choice: you fight for your kin group. But, in at least many parts of the world today, that choice is a choice. 
   Now it may be that these uncomfortable revelations help to explain why we might want to search for a biological or evolutionary for why humans go to war. Maybe that's preferable to the idea that humans just take pleasure in the activity of fighting and pursue it merely for its own sake.
   But just as there's a danger in celebrating warfare and its transcendence, we need to be careful of explaining war merely as an outgrowth of evolutionary necessities, because such explanations can lead to a fatalistic conclusion that war is inevitable. 
   But it's not; the cycle of violence that you see in the Odyssey gets broken all the time in human history. And yes it is much harder to end a war than it is to start one, but it is not impossible.
   When we get carried away by biological explanations we forget that while humans may not have evolved all that much in the past 1,000 years our institutions have. And that's happened because of human choices that go far beyond the desire for food or the need to reproduce.
   Thanks for watching, I'll see you next week.
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