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In which John Green investigates war, and what exactly it may or may not be good for. Was war a result of human beings organizing into larger and more complex agricultural social orders, or did war maybe create agriculture and "civilization?" It's hard to know for sure, but it's sure fun to think about.

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CC Kids:
John Green:
Hi, I'm John Green, this is Crash Course World History and today we are going to talk, for the absolute last time, I promise, about war. Well, this is not the last time that we are going to talk about war because we're going to talk about the twentieth century later -- pretty much defined by war-- but this is the last time we are going to talk about war in an abstract way.

John from the Past:
Mr. Green, Mr. Green! And then we can get to the battles? Because this has been pretty esoteric...

John Green:
Oh, Me-from-the-Past... I remember when I spent thirty minutes with an SAT prep book and emerged with the word esoteric in my vocabulary. But fair enough, Me-from-the-Past, it is a bit esoteric... and you know what else is esoteric? Human existence!

Anyway, in the last episode we examined why individuals might want to go to war and the unspoken assumption in all of that was that war is, you know, on the whole, bad. But is that actually true? I mean, obviously war is tremendously destructive and it can be very bad for the lives of individual humans, but is it possible that violence and war have had a positive effect on human development... or at least some positive effect?


So, as we've discussed previously, wars are usually some type of competition for resources, but war can also lead to cooperation. Like, the earliest examples of war were probably raids, right? And one of the best defenses against a raid is to gather people together in a group. You know... you circle the wagons, you put everybody inside the fort etc.

Some archaeologists actually maintain that human settlements, especially cities, started before agriculture and if that's true then the likeliest explanation is defense. And then there's the fact that agriculture itself has some defensive value, especially when you compare it to, like, herding, because herds are a very inviting target for raids. You know, you can round up all of the cows and make off with them because they can run, but it's hard to, like, rustle twenty tons of wheat.

Plus agriculture usually requires larger concentrations of people, which has a defensive value and, as far as armies go, agriculture provides the resource surpluses that sustain larger groups of warriors.

So, we've often said on CrashCourse World History that agriculture and the cities that came with it were like the beginning of civilization but, in fact, maybe war was the beginning of agriculture.

And then there is the argument that war could be the basis of political leadership. Like, in the ancient world (as in Game of Thrones) successful war leaders build up a retinue of fighters and in order to keep them happy the war leaders needed to supply a constant flow of booty (not that kind of booty - I mean looting, like, the spoils of war).

Anyway, this sets up a need for continuous war because, as your General, the only way I have of paying you is in booty, and we can only get booty if we continue to war.

The people who were best at gathering loot became chiefs and then, through conquests, chiefdom's grew into kingdoms. The examples of this process are too numerous to count and many weren't recorded but the rise of the Zulus in Africa provides a really interesting modern analogy.

The people who would become the Zulu nation were originally Nguni-speaking agriculturalists and herders organized into numerous small chiefdom's until the early 1800's. One of their chiefs Dingiswayo was able to extend his control over the others by his military strength, and then he would often cement his control over these chiefdom's by replacing their chiefs with someone loyal to him - sometimes through a politically expedient marriage (again like Game of Thrones).

Dingiswayo was killed in 1817 and eventually replaced by his military commander Shaka, whose clan name, Zulu, was given to the kingdom. Shaka's military success allowed him to build up a state that eventually controlled quite a lot of territory but he was unable to transition it into a nation state.

So we've seen a little bit of the way that war can change the way that humans can organize themselves, and war, or at least the threat of attack, also may have played a role in the development of city states. 

Lets go to the Thought-Bubble...

Cities began as settlements which, because they were stationary, were targets for raids, and so to deter raiders cities built walls, but those efforts required coordination, or else coercion and resources, which states are good at.

Like Greek city states built walls to defend against constant threats mostly from other Greek city states. Egypt, on the other hand, never developed walled cities because they were relatively free from powerful enemies other than, like, the Assyrians and the Sea-People, and Egypt had fewer internal struggles thanks to the unity provided by the Nile river.

So war shaped city states both physically and politically but city states also shaped war because they changed the ways that wars were fought.

Concentrated urban populations were the basis of civil militias made up of soldiers who were also citizens. That meant that they were both effective fighting forces and political catalysts: they built civic pride and they diminished the power of wealthy warrior elites who wouldn't defeat these new larger armies.

The best example of the citizen militia is probably the Roman Legion, which became so successful at fighting and empire-building that we forget that Rome actually started out as a city state.

[Interrupting himself -] Thanks, Thought-Bubble, although I believe Rome actually got its start when it was founded by two boys raised by a wolf.

But speaking of Rome, let's talk for a minute about empires.

Now, it goes without saying that empires are fairly reliant upon military power... I guess you could also use the dark-side of the force, but even Darth Vader needed Stormtroopers!

But the very nature of an empire is, like, one group of people ruling over many groups of people and to do that you generally do need some military power, whether you're the Persians, or the Romans or even the Mongols.

No, they're not an exception this time, Stan.

But imperial success can backfire when rich empires decide that it's easier or cheaper to have mercenaries do the fighting for them, and because they aren't citizen soldiers they aren't loyal to the state - mercenaries are in it for the loot. And so when you rely upon mercenaries, you need constant war, which can stretch you thin and also those mercenaries aren't loyal to you, and this can be a real problem as the Romans discovered but also many others.

So empires have a ceaseless urge to get bigger but the bigger they get, the more vulnerable they get to both internal problems, like peasant revolts, and external threats like... barbarians.

And this may be why we don't see that many empires anymore, they are expensive and unstable...

...Putin's behind me isn't he...

Putin! Stop building an empire!

So, ultimately in the pre-modern world, wars probably unmade as many states and empires as they made. As Ibn Khaldun put it, "Royal authority is a noble and enjoyable position. It comprises all the good things of the world, the pleasures of the body and the joys of the soul. Therefore, there is, as a rule, great competition for it. It rarely is handed over voluntarily but may be taken away. Thus discord ensues. It leads to war and fighting."

In short, war and the state developed simultaneously and they probably had a reciprocal relationship.

And states are good... ish... I mean, if you're not in the position of being, like, pro-Hunter-gatherer I think that you have to be pro-state. And I'm kind of pro-Hunter-gatherer but I love pizza and the internet and they can't have either!

But anyway, if wars create power and wealth for states, why don't we see that many big, empire-building wars anymore?

[Looks at Putin] I mean, except for you.

Well, one answer actually has to do with wealth. So, warfare changed a lot in the early modern era, after about 1500CE, with the large scale introduction of gun-powder weapons. This has often been called a military revolution because cannon made cities very vulnerable although, in the end, cities proved pretty resourceful, developing new fortification techniques to deal with cannons and, you know, we have cities today despite, like, really excellent cannons.

But anyway, if you've ever watched an episode of Pawn Stars you'll know that cannons are very expensive. 

So the age of gunpowder weapons probably led to states gaining more power of their subjects because in order to pay for all of this military technology they had to modernize their bureaucracies - especially their tax collection system.

So the most successful states were those who could martial their resources to pay for guns and forts and ships and, most importantly, troops, which remain the largest military expenditure.

So now we're beginning to see one of the reasons why Europe would dominate much of the rest of the world after 1500CE and would really dominate after 1850. Europe was raking in money from trade, and especially from colonies which allowed investment in technology and industry that reinforced its military advantages.

Essentially, there was a lot of wealth to extract from the colonies, Europe had the cannons to do so, and extracting that wealth gave them ever better cannons.

And that, my friends, is why here at CrashCourse History we focus more on trade and resources than battles and war.

So this rising cost of armies and navies meant that, increasingly, wealth was power. One of the biggest differences between the pre-modern and modern eras was that, in the former, a state could accumulate wealth through conquest, while in the latter trade is the better and safer bet. Especially exploitative, unfair and unilateral trade with colonies. And then, as trade-reliant states began to eclipse those more reliant on conquests, a funny thing happened.

The rich states that had built their wealth on military might began to shy away from expensive wars. And this was particularly true if the states were considered liberal democracies although, to be fair, liberal democracies are also pretty into war. But at least compared to empires and other kinds of states they seem to be less likely to go to war... he said controversially causing a big explosion in the comments.

Why? Well, the most common answer is that democracies are answerable to constituents who are unlikely to go to war because, you know, dying is bad. But Athens was, like, the purest democracy of all time and also remarkably bellicose. Rome had a fair share of citizen participation and look how peaceful they were.

And then there's the argument that wars became more expensive - Oh! It's time for the open letter! - but first let's see what's in the secret compartment today... Oh, it's an open letter to Military Spending...

Dear Military Spending,

You kind of get a bad rap, or too good of a rap depending on your perspective... Here's the thing, Military Spending, you're one of those people who, like, acts like they've changed so much and they're like totally different from what they were last year, but you're really the same!

It's true that modern armies cost much more than pre-modern ones but modern economies are also much bigger. In fact, as a percentage of state budgets, military spending has remained relatively stable at between 3 and 5% of GDP, even at the height of the Cold War in the 1950's.

You're cool and all, Military Spending, but you're not the reason we have fewer wars.

Best Wishes,

John Green

So, I'd argue that it's not the cost of going to war that has made peace so attractive, it's the benefits of not going to war. Now, the not killing and not dying benefits of obvious but good trade relations with other nations also leads to more stuff for everybody, essentially. This is true for cheap T-shirts and sneakers, but it's also true for, like, medicine and food.

Now, that peace is more economically beneficial than war is not exactly a shocking revelation, nor is it particularly new as John Stewart Mill pointed out...

"Commerce first taught nations to see with good will the wealth and prosperity of one another. Before, the patriot, unless sufficiently advanced in culture to feel the world his country, wished all weak, poor and ill-governed but his own. He now sees in their wealth and progress a direct source of wealth and progress to his own country. It is commerce which is rapidly rendering war obsolete."

Now, you may have noticed that that actually hasn't happened. I'm not going to argue that everything has been peaceful and open-world trade since the end of the Napoleonic Wars, or that capitalist countries seeing war as bad for business have given up on it, but compared to earlier times wars between major powers are much less frequent, a fact that tends to be obscured by the massiveness of the two great wars of the twentieth century. 

So I apologize that this isn't straight-forward military history because I also enjoy a good, glorious battle, but here at CrashCourse we want to provide a framework for thinking about war generally and we want to examine what it says about us as individuals and as social orders - both good and bad.

War may be part of why we have agriculture and cities and states, but, even centuries, John Stewart Mill noticed that is seemed to be outliving its welcome.

Thanks for watching. I'll see you next week.

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