There are lots of Great Internet Debates- over operating systems, video game consoles, or politics.  This last week, a similar sort of name-calling verbal brawl broke out among prominent macro-economists.  But that exchange featured long posts and highly technical arguments.  To simplify it for you, I will summarize the debate as the flame war it was at heart.

Nobel Laureate Paul Krugman: Who is to blame for the failure of economists to respond effectively to this crisis?  Well, there are two types of economists: freshwater and saltwater.  It sure wasn’t us saltwater people, so it must be that the freshwater types are to blame.  They are so detached from reality that they think the Great Depression was just a Great Vacation for workers, resurrecting absurd fallacies I thought we had dispatched for good 70 years ago and thinking they must be right because their ideas are gussied up with fancy equations.  Saltwater Keynesianism is the only game in town.

John Cochrane: Paul Krugman wants us to ignore the last 40 years of work in economics.  In science, he would be the global warming skeptic of the HIV-AIDS denier.  Only a paranoid, calumnous, superficial, idea-less schlock would rely on name-calling and personal attack like he did.  Us freshwater types do not, in fact, deny the reality of bubbles, recessions, and other such real events.  Krugman has no idea what caused the crash, and just advocated fiscal stimulus because he wants the government to be bigger. “So what is Krugman up to? Why become a denier, a skeptic, an apologist for 70 year old ideas, replete with well-known logical fallacies, a pariah… The only explanation that makes sense to me is that Krugman isn’t trying to be an economist, he is trying to be a partisan, political opinion writer…. Krugman wants to be Rush Limbaugh of the Left. I still want to be Milton Friedman, but each is a worthy calling.”

Brad Delong: John Cochrane’s 9-page response had one sentence that was TOTALLY wrong.  The rest of what he said? I don’t feel like talking about it.

Paul Krugman: Nobody likes the freshwater people.  They have no idea what Keynesians even said.  I, by contast, know the literature so well that I finally cited a paper.  Maybe next post I will cite two!

Brad Delong: Freshwater types haven’t read Keynesians?  Of course, but more than that they haven’t read anyone.  They commit fallacies which show they haven’t read Knut Wicksell, Irving Fischer, (fellow Chicago-school monetarist) Milton Friedman, or David Hume’s First Economics Paper Ever.  Today’s Chicago school is an intellectual train-wreck.

Narayana Kockerlakota: What are you talking about guys?  Macro is fine.  If freshwater economists are so clueless why do we dominate the journals and provide most new hires at top universities?  Really there isn’t even a freshwater/saltwater divide anymore.  Here are links to a bunch of papers that Krugman thinks don’t exist, because they are about things he says we ignore.

Brad DeLong: Richard Posner is Uranus!

Justin Wolfers: All these old dudes are just cranky, Narayana is right that the new hires are moving past these problems and these flame wars.  But macro isn’t really ok until the new generation starts paying attention to policy, and policymakers start paying attention to them.

David Levine: Paul Krugman is clueless about economics and just wants to expand government.  It makes me feel physically ill that a distinguished economist could be so ignorant of his own profession.

Brad DeLong: David Levine is so clueless he is not in our galaxy.  His piece is so bad the Huffington Post [not exactly the newspaper of record! JB] should not have published it.

Bob Murphy: A pox on both their houses! Paul Krugman is a jerk and offers horrible policy advice. But John Cochrane’s response is no friend-of-the-court brief in the Austrian critique of Keynesianism.

Scott Sumner: A pox on all their houses! Old Keynesians, New Keynesians, Monetarists, New Classicals, and Austrians are all wrong, and I am right.

Eric Falkenstein: All macro-economists are wrong!  They have tried to fit their business cycle theories to the same ten data points, and the appearance of an eleventh one is not about to solve anything.  It may eliminate some theories, but this is not so helpful since there an infinite number of ways to be wrong.  Macroeconomics is the triumph of hope over experience, and has been no more successful than sociology [the ultimate insult to economists! JB].  At least private companies have figured out how useless this is and stopped hiring macro-economists.

Tyler Cowen: What the hell guys, you really thought you were going to fix macro with a flame war?  I look forward to seeing some peer-reviewed journal articles.

Yoram Bauman: Maybe macro flame wars are a good thing, because the three most terrifying words in the English language are “macro-economists agree that”.  The trouble with macro is built in to the definition of the field: micro-economists are wrong about specific things, while macro-economists are wrong about things in general.

Me: It is a bit traumatic for a young economist like myself to see this go down.  I wonder, why do Mommy and Daddy have to fight like this?  This is weird even by internet standards, because incivility is usually attributed to anonymity, but everyone here uses their real names and goes to the same conferences.  What happened to the good old days when Milton Friedman and Paul Samuelson could lead opposing schools but still be friends?  Do real sciences ever get this divided- was there ever a string theory flame war?  But as economist/comedian Yoram Bauman says, maybe this will turn out for the best.  Perhaps Krugman and Cochrane will do a joint show at the AEA humor session this January in which they reveal that this was all a hoax, and ask whether that wasn’t the most epic trolling ever.  But it seems more likely that the reconciliation will be slow.  Indeed, we may see a repeat of the late 70’s, when the two main factions (Keynesians vs Chicago Monetarists then, New Keynesians vs Chicago Ratex/RBC/New Classicals now) so effectively discredit each other that a third school will seize control of the policy arena.

(Continuing from my previous post, Does the  idea of sustainability survive sustained inquiry?)

Sustainability means preserving good things for future generations.  But as Bob Solow notes, we have no idea what the preferences of future generations are; we are likely to think they are weird.  After all, if someone in 1800 were trying to make people in 2009 better off, what would they do?  Burn less coal?  Would these 2009 people prefer to have more cities, or farms, or picturesque villages, or wilderness (but who likes wilderness? We haven’t had a romantic movement yet, and Thoreau hasn’t even been born)? Certainly we would leave them better off by exterminating dangerous and destructive animals like tigers and wolves.  And we are going a great service to future generations by spreading Christianity and civilization to the backward tribes of the world!

Clearly, it would be pretty hard for a well-meaning person in 1800 to do the right thing from our perspective.  Presumably, the future is also pretty hard for us to figure out.  Solow wisely notes this, then promptly ignores his own advice.

Most blatantly, he says that “control of population growth would probably be the best available policy on behalf of sustainability.”  If he is considering the average utility of the members of future generations then this is at least plausible, although I would not bet on it as the best policy to please weird future people.  But if he is considering the total utility of future people (as I think is proper), then then this is probably nonsense.  A future with 10 billion people will have more happiness than a future with 9 billion people unless those additional people push the world over into famine and resource exhaustion, which seems to me at least highly implausible.  And total utility is the right measure, because considering average utility leads to even more serious moral problems than utilitarianism generally; for instance, it implies that we should euthanize depressed people, or taken to its logical extreme we should euthanize everyone but the happiest person on earth.

But this is an isolated case of Solow being wrong.  Now for the more general theory of his wrongness.  He notes rightly that it is hard to know whether future generations would prefer for us to invest or to preserve the environment, since both are likely to benefit them.   The problem is that he then asserts that both should be categorically superior to present consumption, which can only benefit the current generation.

This disdain for current consumption is at best an oversimplification.  First, we need to distinguish the consumption of non-renewable resources from all other consumption.  In general, this is the consumption that actually makes future generations worse off (by eliminating resources they could have used), and Solow’s idea to count it is a good one (we could subtract the consumption of nonrenewable resources from total GDP to get a measure of “sustainable GDP”, just as economists have sometimes tried to separate out GDP generated from the depreciation of the capital stock).  In some special cases, of course, this consumption could still benefit future generations: the technologies developed for mining are applied more generally, or if today’s resource becomes tomorrow’s nuisance (invasive species?), or if the byproducts of consumption are actually beneficial (say, if future people like a warmer earth then they would appreciate that our consumption lead to CO2 emissions [there is probably a better example of this idea]).

But most consumption does not involve (at least directly) the use of nonrenewable resources.  If I consume a lot of perishable, rival goods like corn or trees, people in the future could simply grow more.  This sort of consumption is something people in 100 years would, in most cases view neutrally.

Most interestingly, there is the consumption of non-rival goods.  Will people in 100 years be worse off because I read too many books, or watched too many movies, saw too many plays, listened to too many concerts?  Not at all.  In fact, to the extent that such consumption encourages the creation and preservation of such non-rival, not-very-perishable goods, it actually benefits future generations! Again of course there are exceptions, many people in the 20th century would have been better off if Lenin et al hadn’t bought Karl Marx’s books, and it is hard to imagine much current music being of any benefit to future generations.  But in general the consumption of art and writing can be of great benefit to future generations.

Back to the general theory.  Think of someone living in Athens in the golden age of Greece.  What could they do to be of most benefit to future generations?  Solow suggests that we would value their environmental protection and their investment.  Well, I certainly don’t mind that they invested; I’m sure they enjoyed operating capital-intensive olive oil businesses.  I suppose it is good that they protected their environment, though I might enjoy Greece more if they had turned more non-renewable marble into buildings and statues.  But what I, weird future-person, value most from average ancient Greeks is their consumption- the fact that there was a market for Plato’s dialogues, Aristophanes’ plays, and Herodotus’ histories.  This same applies to Renaissance patrons of the arts, classical concert-goers, the book-buying public of the Enlightenment and the modern era.

In a way, I suppose this blind spot for the incredible power of ideas, information, and other non-rival goods should be expected from Solow, whose namesake growth model sees technology as exogenous!  But given that the development of ideas and technology really does depend partly on the knowledge that people will pay to consume them, I am glad that people in the past undertook that consumption and left us with the treasure trove of ideas we have.

In Bob Solow’s 1993 “Economist’s Perspective on Sustainability“, it survives as a “necessarily vague, but useful” idea.  He notes that sustainability has been conflated with other moral ideas about environmental protection, but that sustainability itself does not necessarily mean preserving species or wilderness.  Instead it is about “distributional equity” between the present and the future.  This means that we should be comparing general standards of living- how much are we better off because we make future generations worse off- rather than only the status of the environment.

To Solow, this means that future generations will value our investments as well as our preservation of resources, so they would not necessarily want us to preserve resources at the expense of investment; but he does say that both investment and resource preservation should be preferable to consumption.

His best idea is to clarify all this by looking at the sustainability of past generations.  We are talking about doing well by future generations, but to past people we are one of those future generations!  Are we happy with how sustainable our predecessors’ economy was?

Well, they killed off the dodos and mammoths, used up most of the oil in the continental US, and left a lot of toxic chemicals lying around; so in the purely environmental sense, they did not do very well.  But in a broader sense, they did fine by us; in fact, I think we got the much better end of the deal.  We have a vastly higher standard of living than people did 50 or 100 or 10000 years ago; inter-temporal distributional equity would actually entail more past environmental degradation insofar as it allowed our very poor ancestors a higher standard of living.

This same logic implies that we should worry less about developing countries like China raising their living standards though industrial pollution, since future Chinese people (as well as current and future moralizing Westerners) will have better living standards even after resource degradation and pollution has been accounted for.

Certainly, I am happy that past generations built Philadelphia rather than leaving forests, built Paris rather than leaving plains, built Boston rather than leaving us swamps to enjoy.  I would like to have mammoths around to look at in zoos (or hunt?!!), but I am sure that prehistoric hunter-gatherers got a lot more enjoyment from not starving than I would from having a better zoo.

Perhaps there is some inherent moral value to not polluting, or to preserving wilderness, or (most plausibly) to not causing species to go extinct.  But this is a different thing than sustainability for the sake of future generations of humans; it is instead about valuing other species, or the environment generally, inherently and for their own sake.  Which is another discussion entirely!

Through all this I am on board with Solow.  In my next post, I will show how Solow gets things a bit wrong through oversimplification.

After the American Revolution, democracy was the new thing that all the cool Americans were doing.

In the 1960’s and 70’s, a large youth cohort and a constitutional amendment lowering the voting age brought down the age of the median political participant.  Political policies and styles became more in tune with the youngest generation which is the eternal font of cool.

Now the youth cohort is small but technology is multiplying their influence.

Two recent examples deal with symbolic bills rather than policy but demonstrate this so perfectly.

First, the Oklahoma State Legislature decided to choose the Official Rock Song of Oklahoma using an internet poll.  In an upset over many classics and many songs that had more to do with the state, the winner was the Flaming Lips’ “Do You Realize” (which can be found on the video page of the band’s website).

Second, the creators of the gaming webcomic Penny Arcade just got commended by the Washington State Legislature.

This officially ushers in the age of hip techno-democracy!

David Brooks’ NYT column introduces a useful framework for evaluating the stimulus and economic policy.  In the short term this a welcome exhortation for less grandiose plans.  In the medium term, the stimulus and bailout packages will provide an excellent test for the potential of government planning.  I hope people will look back two and five years from now at our current economic policies using the lenses provided in the column.  An except:

President Obama has concentrated enormous power on a few aides in the West Wing of the White House. These aides are unrolling a rapid string of plans: to create three million jobs, to redesign the health care system, to save the auto industry, to revive the housing industry, to reinvent the energy sector, to revitalize the banks, to reform the schools — and to do it all while cutting the deficit in half.

If ever this kind of domestic revolution were possible, this is the time and these are the people to do it. The crisis demands a large response. The people around Obama are smart and sober. Their plans are bold but seem supple and chastened by a realistic sensibility.

Yet they set off my Burkean alarm bells. I fear that in trying to do everything at once, they will do nothing well. I fear that we have a group of people who haven’t even learned to use their new phone system trying to redesign half the U.S. economy.

We can all think of specific times when a political party has shot themselves and their base in the foot.  In fact, the last eight years may have been one of these times.

If we believe what most say, that power corrupts, then any party long in power will get old and corrupt.  There is no one party, or set of ideas, which can govern well indefinitely; that is not how human nature works.  They must eventually be replaced by new people and new ideas.  In traditional political systems this could be accomplished through royal marriage to outsiders, or weak regimes being conquered, or revolution.  In a liberal democracy, the new regime can be voted in.

There will always be new political challenges that call for new leadership.  But there are also old challenges that emerge anew.  Some problems may move in a cyclical manner.  I posit that inequality is one of these.

For many voters (though not myself), relative equality is an important consideration; even if no one is starving, it is wrong or obscene for a CEO to make 400 times the pay of his company’s janitor.

In a place where inequality is greater, these voters are more likely to support policies which reduce inequality; where inequality is less of a problem, voters will not support redistributionist policies so strongly.  As these policies take effect, they will change the political reality and bring about the end of the economic reality which gave them political life.

Suppose one party, lets call them Republicans, became associated with policies which brought inequality, while another party, call them Democrats, became associated with redistributionalist policies to reduce inequality.  These parties, if strongly associated with these policies, could become tied up in the back-and-forth political cycle of equality.  So if Republican tax policies over the past 8 years increased inequality in America, then Republicans faced a more hostile political environment of their own creation.

David Frum in the New York Times from puts forward a similar thesis from an explicitly conservative perspective and with loads of anecdotal evidence.  This theory deserves further investigation using rigorous statistical analysis, comparing data on inequality at the most local level available with election results at static points in time, and how changes in inequality over an election cycle or over longer periods affects results.

You’ve got to read P.J. O’Rourke’s essay in the Weekly Standard, “We Blew It”.  The whole conservative and Republican establishments are trying to figure out what went wrong and what to do next; this is one of the best attempts at the former.

Excerpts:

“It took a Democratic majority in the House of Representatives 40 years–from 1954 to 1994–to get that corrupt and arrogant. And we managed it in just 12“

“Conservatives should never say to voters, “We can lower your taxes.” Conservatives should say to voters, “You can raise spending. You, the electorate, can, if you choose, have an infinite number of elaborate and expensive government programs. But we, the government, will have to pay for those programs. We have three ways to pay.

“We can inflate the currency, destroying your ability to plan for the future, wrecking the nation’s culture of thrift and common sense, and giving free rein to scallywags to borrow money for worthless scams and pay it back 10 cents on the dollar.

“We can raise taxes. If the taxes are levied across the board, money will be taken from everyone’s pocket, the economy will stagnate, and the poorest and least advantaged will be harmed the most. If the taxes are levied only on the wealthy, money will be taken from wealthy people’s pockets, hampering their capacity to make loans and investments, the economy will stagnate, and the poorest and the least advantaged will be harmed the most.

“And we can borrow, building up a massive national debt. This will cause all of the above things to happen plus it will fund Red Chinese nuclear submarines that will be popping up in San Francisco Bay to get some decent Szechwan take-out.”

Yes, this would make for longer and less pithy stump speeches. But we’d be showing ourselves to be men and women of principle. It might cost us, short-term. We might get knocked down for not whoring after bioenergy votes in the Iowa caucuses. But at least we wouldn’t land on our scruples. And we could get up again with dignity intact, dust ourselves off, and take another punch at the liberal bully-boys who want to snatch the citizenry’s freedom and tuck that freedom, like a trophy feather, into the hatbands of their greasy political bowlers.”

The man remembered for Sherlock Holmes was not only a novelist, but a contemporary historian as well.

Searching for a good history of WWI in the Widener Library, I stumbled across his 5-volume his of the war. I decided to see whether his writing ability carried over to this new field.

One might expect that a man famous as a novelist would deliver a gripping narrative full of beautiful prose, but one lacking in historical accuracy and a thorough understanding of the political situation and military tactics.

One would, however, be wrong on all counts.

Conan Doyle wrote 1914 like a traditional historian. His prose mostly consists of precise descriptions of military actions- X unit attacked Y place on D date for R reason, and sustained ABC casualties. But he demonstrates a thorough knowledge of tactics, strategy and politics.

1914 was written and published in 1916, while the war still raged. Conan Doyle admits that his narrative is handicapped by a lack of information about the enemy and the allies. For this reason, his focus is on the British Expeditionary Force.

For a book written during an ongoing war, it is surprisingly fair. The author continually praises the courage of the German forces. He admits that “Germany was grievously handicapped at sea, and that she deserves the more credit for whatever she accomplished.” The book is not exactly wartime propoganda. His criticisms of Germany are restricted to the same sort impartial people made in hindsight- that invading a small, neutral country, sinking civilian ships, and wearing enemy uniforms are not good things to do. When he does editorialize, however, his words are passionate:

“The German representative at Brussels was perjuring his soul”

“The long-meditated crime had been done, and, with loud appeals to God, Germany began her fateful campaignby deliberate perjury and arrogant disdain for treaties. God accepted the appeal, and swiftly showed how the weakest State with absolute right upon its side may bring to naught all the crafty plottings of the strong.”

The author, like so many others, struggled to understand why the war started, and especially what could have brought English and Germans to fight each other.

“Up to the year 1896 there was a great deal of sympathy and of respect in Great Britain for the German Empire. It was felt that of all Continental Powers she was the one which was most nearly allied to Britain in blood, religion and character.”

He expressed continued consternation that two branches of the German race should be warring against one another, that the Saxons who went upriver should, after only 1500 years, be so different from those who went across the sea. He notes how English regiments would find on the corpses of their Hanoverian enemies insignia matching their own, from campaigns when they had served together.

He lays the blame for the English-German estrangement on the Kaiser, the construction of a massive German navy- and on the most dangerous people of all, fellow writers.

“a number of writers, of whom Nietzsche and Treitschke are the best known, had inoculated the German spirit with a most mischievous philosophy, which grew the more rapidly as it was dropped into the favourable soil of Prussian militarism. Nietzsche’s doctrines were a mere general defence of might as against right, and of violent brutality against everything which we associate with Christianity and Civilization….. The typical brute whom he exalted was blond, but a brute of any other tint would presumably suffice. It was different in the case of Treitschke….. he taught the rising generation of Germans that their special task was to have a reckoning with England and to destroy the British Empire, which for some reason he imagined to be degenerate and corrupt.”

Writing often exerts a power of the minds of men. With such power comes the potential for great danger. Why is it that the German writers of the nineteenth century, Nietzsche, Trietschke, and Marx, could sow so much sorrow in the twentieth? Will books of such power, for good or evil, ever again be written?

Moving back to more definite matters. As he wrote this book in 1916, Arthur Conan Doyle could still speak unashamedly of war in terms of honor and chivalry. He constantly praises self-sacrificing courage on the part of the troops. He refers hundreds of times to “gallant” officers, even as the absurdly high casualty rate meant that most references were to their deaths. Modern war, with its accurate rifles and its machine guns, did not permit many people to survive long enough for a real narrative to coalesce around them. But the author tries his best to see purpose and courage and avoid the words like “pointless”, “futile”, and “stupid”, to which men would soon turn. He could still speak of

“the days when the high gods of virility would smile as they looked down upon the chosen children of Odin, the English and the Germans, locked in the joy of battle.”

My last post was a lengthy attempt to explain how the two World Wars changed Europeans’ philosophy, making another major European war unlikely.

In this post I will propose a shorter, simpler explanation.

It’s all about technology.

Before World War One, the logistics of transportation and supply did not allow for large armies to take the field. From the First World War on, each major combatant was able to send millions to war, greatly expanding the amount of casualties possible. Combined with new weapons like poison gas and machine guns, this meant war killed more soldiers, faster than ever before.

People had second thoughts about going to war.

World War Two brought the carnage home with massive fleets of powerful bombers. Going to war meant not only risking the lives of millions of young men, but also the entire infrastructure, economy, government, indeed the entire civilian population- every man, woman and child was in danger of the rain of steel and fire.

The benefits of winning a war have stayed relatively constant over history; indeed, they have diminished as the structure of the economy makes plunder relatively less lucrative. But the cost of losing, and the cost of fighting at all no matter the outcome, have risen dramatically.

“Total” war, where everyone is a target, means war isn’t a very good deal. People really started to look for other ways to solve problems.

Then came the Cold War, when both sides had large nuclear arsenals. Now not only were soldiers bound to be killed, not only were the civilians of the combatants afraid of being bombed; now those who would start a war were forced to consider the possibility that they might annihilate the entire human race.

Major European wars, where both sides possessed weapons of such power, became really bad ideas.

People changed their philosophies, morals, and world-views as necessary to ensure their continued survival.

Now Europeans sort out political issues by arguing in Brussels, and reserve their aggression for soccer riots.

The atomic world is a bright one after all.

The memory of the Great European War, of millions of young men fighting and dying to win a few yards of shell-pocked mud, was enough to convince many that war was an ugly, irrational, pointless endeavor which civilized nations should have the good sense to avoid in perpetuity.  They hoped that something good could emerge from the mass of suffering, that this worst of all wars would also be the last.

Modern minds, in the knowledge that this war would only be the First to earn the dubious honor of being a “world war”, have looked back on the inter-war idealism as hopelessly naive.  I myself have ridiculed their dream, and still do feel safe predicting that wars will be with us for some time yet.

But in some sense, the dreamers and pacifists were right.  World War One did not instantly bring perpetual peace.  But it was the beginning of the end for European war.

In the ninety years since World War One, only a single inter-state war has erupted in Western or Central Europe, and the prospect of another seems quite unlikely.  The length of the peace and the current absence of plausible threats to it marks a major departure from millenia of European history, a history often remembered as one war after another.

There remained only one detour on the road to peace.  World War Two would wrest from the First World War the grim title of deadliest war of all time.  New technology and extreme mobility meant that the Second World War would be fought very differently.  But while the how of the war was very different, the why was largely the same.  The unification of Germany fundamentally changed the geopolitical balance of Europe.  The Germans thought that their newfound strength deserved recognition.  The spirit of the age was one of imperialism and social Darwinism.  German philosophers had spent a century glorifying the will to power and dismissing morality as born of slavery and meant for the weak.

Before each World War, the geopolitical situation of a rising Germany able to dominate its neighbors combined with a philosophical and ideological situation which made Germans willing to invade their neighbors.  Just as with previous attempts by the Hapsburgs and the French to establish European hegemony, Germany’s naked desire to dominate the Continent inspired her neighbors, individually less powerful that her, to form coalitions able to defeat her.  Geopolitics functioned as always.  Fundamental change came not when the European map was redrawn for the thousandth time, but when the hearts and minds of Europeans were realigned.

Human beings are naturally aggressive, and tend to cluster into groups distrustful of outsiders.  A disposition toward war is bred into our very beings.  It is there in babies jealous for food, there in children fighting in streets and in playgrounds.  This tendency from our nature requires a strong dose of “nurture” if it is to be overcome.  Instead many children of the time learned from parents and teachers that war was honorable and glorious and that other countries were untrustworthy and must be taught respect.  Nurture, rather than fighting the worst tendencies of nature, reinforced them.

World War One drove people to deeply question the beliefs that allowed such a war to take place.  Germany had sent a generation to die on French soil and gained nothing.  Germans questioned their beliefs, but in the end elected a man who give their beliefs one more try, saying in essence- we had the right idea, we just didn’t try hard enough.  So they did try harder, they even succeeded in conquering France.  But a second defeat, this time with Germany not only bled dry but also bombed out and occupied, finally convinced them.  They didn’t need to fight harder, or come up with a better plan of invasion; they needed a total gestalt shift.  They needed to look at their neighbors and see people like themselves, people who could be lived with.

You put you hand into a fire and it gets burned.  You might wonder if your technique of fire-touching was incorrect.  The more scientifically minded way wonder if fire caused pain or was only sometimes correlated with it.  But if you get burned again, and worse than the first time, you learn your lesson, and stop touching the flame, lest it consume you.  It took two World Wars, but Germany and Europe along with them learned their lesson.  The next geopolitical imbalance, pitting the U.S. and Western Europe against the Soviet Union and Eastern Europe, lasted forty years, but saw no no major war.  The Americans and the Russians had learned along with Europe, and saw major wars in Europe as a very last resort.  Gone were the days when a European nation would dare to, or even desire to invade their neighbor.