Why did Putin invade Ukraine?
A full-on Russian invasion of Ukraine seemed unlikely; game theory might help explain why Vladimir Putin went through with it.

Executive editor
Hi Quartz members,
For as long as people have written about war, theyāve argued over how to explain it. Is war caused by the desires, obsessions, and failings of the people in charge? Or is it the result of circumstances and incentives? Zoom in? Or zoom out?
Just two weeks ago, the trade-offs for Russia of a full-on Ukraine invasion made its likelihood seem low. So why did Putin invade? New York Times columnist Tom Friedman took the zoomed-in view to an extreme, writing thatĀ āThe only place to be for understanding this war is inside Russian president Vladimir Putinās head.ā A more nuanced version comes from Brookings fellow Fiona Hill, who in her biography Mr. Putin describes a key aspect of her subjectās identity as his āfirm conviction that his personal destiny is intertwined with that of the Russian state and its past.ā
In other words: To understand the war, understand the person waging it.
But āpolitical scientists are trained not to think about leaders,ā says Gautam Mukunda, a political scientist at Harvard Business School whose research does focus on leadership. Instead, many of them prefer the logic of power and incentives. For example, āthe idea of Ukraine in NATO is something that every Russian leader of any political stripe would find to be unacceptable,ā says Mukunda. āThatās not unique to Putin.ā
And if Putin misjudged the resolve of both Ukraine and NATO, thatās not unusual either, according to Chris Blattman, an economist at the University of Chicago and author of the forthcoming book Why We Fight. One of the most common reasons adversaries go to war, he argues, is because they canāt adequately judge each othersā strength, and each side is overconfident. Fighting reveals valuable information. Until last week, for example, it wasnāt clear how far Germany would go in supporting sanctions. āThis is how you find out,ā Blattman told Quartz. āYou invade. Most wars, when they happen, are short. Because all this stuff gets revealed.ā
In the case of Russia, itās even harder than usual to separate the leader from the circumstances: After more than 20 years of Putin rule, they are two sides of the same coin. āPower changes who people are,ā says Mukunda. āIt makes them more aggressive, more Machiavellian, more manipulative. For most people, it makes them worse.ā
5 theories of war
In Why We Fight, Blattman uses game theory to explain why war does and doesnāt happen. His starting point is that war is rare because itās expensive. But five factors can overwhelm the incentives for peace:
šŖĀ Unchecked interests. War is more likely when the people in charge donāt pay the price for it. Thatās almost always true to an extent, but some leaders are more or less insulated from the costs of conflict.
š²Ā Uncertainty. Neither side knows for sure how strong the other is. One side could be bluffing about its strength or resolve, so sometimes the other side calls.
šļøĀ Commitment problems. When one side is growing stronger, the other may want to attack before its adversary gets too powerful. The growing power might promise not to attack later on when itās the dominant power, but that commitment canāt be trusted.
š¤Ā Misperceptions.Ā Decision makers are overconfident and donāt understand how their adversaries think.
š¤Ā Intangible incentives. Sometimes people care about things that canāt be bargained for and go beyond costs and benefitsālike vengeance, glory, or freedom.
3 theories of Putin

In their book Mr. Putin, Fiona Hill and her Brookings colleague Clifford Gaddy mine Putinās biography and sketch three core āidentitiesā that define his approach to power.
- The statist. Putin came to power when āmany internal observers feared Russia was in danger of total collapse.ā He pledged to restore order by restoring the power of the state.
- The āhistory man.ā An avid reader of history, he sees himself as connected to Russiaās long imperial pastāand shapes how Russian history is presented to suit his purposes.
- The survivalist. Through his own experiences and those of his country, Putin absorbed the importance of flexibility and preparation for worst-case scenarios. Among other things, it drives his commitment to building large reserves of foreign currency.
Why Putin invaded
Melinda Haring, deputy director of the Atlantic Councilās Eurasia Center, was not surprised when Russia invaded Ukraine. In November, she warned that āPutin will strike Ukraine again, and soon.ā Hereās why she thinks Putin took the risk:
- He felt insulated from sanctions because heād built up a large reserve of foreign currency. Historic sanctions that prevent some of that reserve from being used will test his theory.
- He misunderstood Ukraine. Putin underestimated how much Ukrainians value independence and expected minimal resistance.
- He perceived Western weakness. āPutin may not feel invincible,ā Haring wrote in November, ābut when he looks at a leaderless Europe and the domestic chaos in the United States, heās confident that he has a free hand in eastern Europe.ā
- He was tired of dealing with Zelenskyy. The young president was inexperienced and Ukraine was the weaker nation; Putin āwas frustrated that he couldnāt get a deal.ā
- He believed time was against him. āUkraine is changing,ā Haring told Quartz, āand if he doesnāt intervene now, Ukraine will no longer be in his sphere of influence.ā
- He wants his legacy to include territorial expansion. āGreatness in Russian history is measured by territorial conquests, not GDP,ā Haring writes.
What to watch for next
- āItās all about Kyiv,ā says Haring. A 40-mile convoy of Russian tanks headed for Ukraineās capital had made ālittle discernible progressā as of Thursday, according to UK officials. But that could change, and experts caution against underestimating Russiaās military based on the past week.
- More sanctions could be coming. Two areas to watch: The US and EU could expand āsecondary sanctionsā against countries doing business with Russia. Or they could include energy, the most important exemption to date. That would require Europe to quickly find alternatives to Russian gas.
- Whatās the off-ramp? There are multiple justifications for sanctions, as political scientist Dan Drezner notes, but āIf the goal is to compel [Russia to change its behavior], then the sanctioners need to be explicit about what Russia can do to get the sanctions lifted.ā Noah Smith writes that āEU leaders and Biden need to announce clearly and repeatedly that if Russian troops pull back from Ukraine, the sanctions will all be quickly dropped.ā Would that be enough? Or would the West demand reparations?
- Mondayās Forecast email. Weāll dive into the current financial warfare, and where it goes next.
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š„Ā The world is getting climate change adaptation wrong
š§Ā How sanctions are squeezing the Russian middle classĀ
ā²ļøĀ Thereās a job perk more popular than four-day workweeks
šŗš¦Ā A cheap drone is giving Ukraineās military an edge
š¶Ā Can āparentingā go on your resume? LinkedIn says yes
š¢ļøĀ How Europe could quickly cut its Russian gas use by a third
š¤Ā Large employers are womenās best hope for fertility benefits
5 great stories from elsewhere
š§ Ā How do you solve a problem like the internet? Web3 is often touted as the more open, more free, and less centralized internet of the future. But itās still selling a āpromise we were sold a decade or so ago,ā Colin Horgan writes in OneZero, āthat the more weāre connected, the more trust would be created.ā And who still believes that?
š¬Ā A chat with Mohammed bin Salman. In an interview with The Atlantic, the crown price of Saudi Arabia defends holding Saudi officials hostage in the Ritz-Carlton and says Washington Post columnist Jamal Khashoggiāwhose 2018 murder MBS is accused of orderingāāwould not even be among the top 1,000 peopleā on his hit list.
š¦ Ā McDonaldās hard line on soft-serve. One in seven US McDonaldās ice cream machines is out of commission⦠so why is the fast food giant telling franchisees to ditch Kytch, whose devices help fix them? āTheyāve tarnished our name,ā Kytch co-founder Melissa Nelson tells Wired; sheās suing for $900 million.
šæ Ā New life for āzombie urchins.ā Purple sea urchins are known for devouring kelp forests, and a series of environmental phenomena have them proliferating in California. But what if a pest could become a delicacy? The Los Angeles Times look at how urchins fattened up to produce fresh roe for restaurants are giving the species new purpose.
šĀ Does my son know you? āI donāt want Jackson to have the same childhood that I did,ā Jonathan Tjarks writes in a beautiful post for The Ringer about his terminal cancer diagnosis. āI want him to wonder why his dadās friends always come over and shoot hoops with him. Why they always invite him to their houses. Why there are so many of them at his games.ā
Thanks for reading! And donāt hesitate to reach out with comments, questions, or topics you want to know more about.
Best wishes for a conflict-free weekend,
āWalter Frick, executive editor
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