⭐︎Summary⭐︎ Explaining "How States Think" in a way even elementary school students can understand (Book)

How States Think

The Rationality of Foreign Policy

Authors: John J. Mearsheimer and Sebastian Rosato

This book answers a very big question: "When national leaders start a war, are they really thinking it through properly? Or have they gone crazy?"

Have you ever watched the news recently and thought, "Why would they do something so terrible? Are they crazy?"

Actually, many adults think the same thing.

For example, when the Russian president attacked Ukraine, the British Prime Minister and American politicians said, "He is irrational (he isn't thinking properly)."

However, the authors of this book say, "No, that's not right. In most cases, national leaders are making decisions very seriously and logically."

This is called being "rational."

Today, I will explain the true meaning of the word "rational" and how major historical events were decided.

Chapter 1: What does "rational" mean?

First, let's clarify the meaning of the word "rational."

When you hear "rational," you might think it means "doing the right thing" or "being successful."

However, it is used with a slightly different meaning in this book.

The authors state that for a state to be "rational," two conditions must be met:

■ 1. Based on a "credible theory":

This refers to a convincing explanation or plan that says, "The world works this way, so if we do this, it should work out."

It must be based on realistic thinking, not just a whim or superstition.

■ 2. "Deliberation" (discussing it with others):

This means that the leader does not decide things on their own, but rather engages in intense debate with advisors and experts, going back and forth to reach a decision.

If these two things are in place, even if the result of that decision ends in 'failure,' the country can be said to have been 'rational'.

This is a very important point.

'Results' and 'processes (ways of thinking)' are different things.

Even if you studied hard for a test but happened to have a stomachache and got a bad score, the fact that you 'studied (the process)' was rational, right?

It is the same with this.

Conversely, it is 'irrational' for a leader to decide things alone without listening to anyone's opinion, or to act based on believing in impossible dreams that cannot exist in reality.

Chapter 2: The World is Shrouded in 'Fog'

Why are 'solid theories' and 'discussion' important for a country? It is because the world of international politics is 'uncertain'.

'Uncertainty' is different from the 'probability (risk)' of rolling dice. With dice, you can calculate that 'the probability of rolling a 1 is one-sixth,' right?

However, in the world of international politics, important information—such as 'what the other country is actually thinking' or 'what kind of new weapons will be created in five years'—is lacking, so you cannot even calculate it. It is like walking through a pitch-black fog.

You cannot find the answer using only data and formulas (called expected utility maximization). That is precisely why leaders try to move through the fog using 'reliable theories (maps for understanding the world)'.

Chapter 3: Did Japan Start the War 'Rationally'?

Now, let's look at real examples from history. You may know about the 'Pearl Harbor attack,' where Japan went to war with the United States, from your history classes.

Many people tend to think, 'Challenging such a strong and large America to war—the leaders of old Japan must have been reckless and out of their minds (irrational).' However, the authors of this book analyze that 'Japan at the time was rational'.

What does that mean?

In 1941, Japan was very cornered. The United States had cut off important resources like oil (oil embargo). Without oil, factories cannot run, and ships and planes cannot move.

Japan's leaders held meetings over and over again to discuss this. These were called 'Liaison Conferences' or 'Imperial Conferences.' They thought as follows:

'If we do nothing, Japan will run out of resources and will not be able to survive as a nation (slow death). We would have no choice but to do whatever America says. But if we fight now, even if the chance of winning is small, there might still be a possibility of survival.'

In other words, they weighed 'perishing by doing nothing' against 'the dangerous path of fighting to survive,' and logically chose the latter.

They were not delusional, thinking they would 'definitely win.' Rather, they understood that 'winning would be difficult'.

Even so, they made their decision based on the theory of 'balance of power,' which is essential for a nation's survival.

As a result, Japan lost, but this book explains that the decision-making process itself was 'rational,' based on solid theory and discussion.

Chapter 4: Germany's Dilemma in World War I

Next, let's talk about Germany starting World War I back in 1914. It is often said that 'Germany started a reckless war,' but that is actually not the case.

At the time, Germany felt terrified that its neighbor, Russia, was becoming increasingly powerful.

Germany's leaders thought, 'We are stronger now, but in a few years, Russia will become too powerful, and Germany will lose.'

So, they used the theory of 'preventive war.'

This is the idea of 'fighting and winning now before the opponent becomes too strong and it is too late.' The German emperor and generals gathered to analyze the situation in detail and discuss it. As a result, they reached the conclusion that 'we have no choice but to fight now.'

This also ended in Germany's defeat, but given their situation and the information they had at the time, it was a logical and rational judgment.

Chapter 5: The United States and the Cuban Crisis

There is also the 'Cuban Missile Crisis' of 1962, which is closer to modern times.

This was an incident where the Soviet Union (a country like today's Russia) tried to place nuclear missiles on the island of Cuba, right next to the United States. It was a crisis that could have led to nuclear war and the extinction of humanity.

At this time, President Kennedy of the United States acted very 'rationally.'

He held meetings called 'ExComm,' where he gathered many experts to discuss the situation every day.

Hardline opinions like 'We should bomb and destroy the missiles immediately!' clashed with cautious opinions like 'No, we should solve this through discussion.'

President Kennedy did not force his own opinion; instead, he listened carefully to everyone's views and ultimately chose a cautious method to avoid war: a 'naval blockade' (surrounding the sea with ships to prevent Soviet vessels from passing).

This is a very good, rational example based on thorough discussion (deliberation) among everyone on how to avoid nuclear war.

Chapter 6: An 'Irrational' Example That Failed

So, are there any examples that were 'not rational' (where a bad decision-making method was used)?

Yes, there are.

The author provides several examples, one of which is the 2003 'Iraq War.' President George W. Bush of the United States decided to attack the country of Iraq. However, the way this decision was made was vastly different from the Cuban Missile Crisis mentioned earlier.

First, President Bush and a small group of people around him (such as Vice President Cheney) believed in theories like the 'domino theory' and 'forced democratization,' thinking that 'if we attack Iraq, it will immediately become a wonderful democratic country, and the entire Middle East will become peaceful.'

However, looking at history, it was clear that trying to force democracy through war would not work well.

In other words, their theory was 'not credible.' Even worse, they did not engage in 'discussion.'

They ignored the opinions of experts who opposed the war and hid inconvenient data. President Bush said, 'I have already decided,' and did not allow for debate.

As a result, the United States won in Iraq, but the subsequent Iraq fell into chaos, and things did not go according to plan.

This is an 'irrational' example where a leader decided arbitrarily and used a bad theory. The author calls such a leader a 'Dominator.'

Chapter 7: The most important goal for a nation is 'survival'

So far, we have talked about 'how a nation decides (process).' Finally, I will talk about 'what a nation aims for (goal).'

Nations have various goals.

These include 'wanting to become wealthy (prosperity)' and 'wanting to spread their own ideas (ideology).' However, there is one most important, non-negotiable goal.

That is 'survival.'

Just like humans, if a nation dies (is destroyed), it cannot become wealthy or express its opinions.

Therefore, no matter how profitable a deal may be, or no matter how much of an ideal they want to spread, if it leads to the destruction of the nation, a rational nation will not choose it.

For example, regarding the issue of the island of Taiwan, China says, 'If Taiwan becomes independent, we will go to war even if it means a huge economic loss.'

This is because they prioritize 'protecting the form of the nation (survival)' over 'money.'

During World War II, Britain disliked the Soviet Union, which was communist (a different way of thinking from their own), but in order to survive against the powerful enemy of Nazi Germany, they joined hands with the Soviet Union, whom they disliked.

This was also a rational action that prioritized 'survival' over 'likes and dislikes.'

In this way, nations are always thinking about 'survival' as their top priority when they act.

Summary: Why learn this?

The most important thing this book teaches us is that "even if another country is acting in a way we cannot understand, there must be a 'rational reason' they have thought through desperately in their own way."

When we see people with different ideas from our own, we tend to immediately think, "That person is stupid" or "They are crazy."

However, President Putin, as well as leaders of Japan in the past, were making decisions based on specific theories and discussions with their peers in order for their countries to survive within the situations of their respective times.

Of course, that does not mean that "it is okay to go to war." Even if something is rational, it can still lead to terrifying or tragic results.

This is because rationality is separate from "morality (whether something is good or bad)."

But if we want to prevent war and create peace, it is important not to just dismiss the other side as "crazy," but to imagine what is inside their heads (how the nation thinks) by asking, "What kind of theory (map) do they have?" or "What kind of fear are they feeling?"

If we understand that the other side is being rational, we can also predict their movements.

This book gives us a very powerful lens to decipher international politics news, which may seem difficult at first glance, using "logic" rather than "emotion."

When you watch the news from now on, please try to think, "Based on what kind of theory and what kind of discussions did the leader of this country decide this?"

If you do that, the way you see the world will surely change.

⭐️Appendix⭐️ Audio Analysis

How to Grasp the Rationality of a Nation—Theory-Based Decision Making and Cognitive Limits (Transcript of Audio Analysis)

Abstract: In international politics, it has been repeatedly questioned whether nations act based on calm calculations or are swayed by assumptions and emotions. This paper organizes the importance of theory-based judgment and deliberation, focusing on the perspective of grasping national rationality not through "results" but through the "decision-making process."

At the same time, it examines the possibility that bounded rationality, heuristics, analogies, and groupthink may distort decision-making. Furthermore, referring to the framework presented in "How Nations Think: The Rationality of Foreign Policy," it clarifies the conditions under which rationality holds and fails, using the contrasting cases of the Pearl Harbor attack and the 2003 invasion of Iraq.

In conclusion, it argues that while nations often attempt to behave rationally through theory and deliberation, there is always room for irrationality to enter due to crises or organizational dynamics.

Keywords: Rationality, reliable theory, deliberation, uncertainty, bounded rationality

1. Introduction: Why do nations start wars that, in hindsight, seem self-destructive? This question has created a clash between the traditional view of the nation as a single decision-making entity and the view that focuses on the cognitive limits of humans. The former assumes that nations must rationally choose strategies based on theory to survive in a world where security comes at a high price. The latter views that policy is made by humans, who tend to rely on shortcut thinking in situations where time and information are scarce.

The conflict between the two is also reflected in how real-world events are interpreted. For example, when a war ends in defeat, the conclusion changes depending on whether one sees it as evidence of irrationality or as a rational thought process where the conditions collapsed. This paper aims not to simply dichotomize the two, but to organize the conditions that support rationality and the paths through which irrationality enters.

2. Definition of Rationality: Process, Not Result: Rationality is not synonymous with success or failure. Policies thought out rationally can fail due to unforeseen factors or uncontrollable constraints. Also, rationality is separate from morality. Even policies that are criticized can be designed based on a certain theory to achieve a goal. Therefore, the focus of evaluation must be placed on the decision-making process.

Rationality here consists of two conditions. First, the strategy must be based on a reliable theory. I consider a theory to be an explanatory framework equipped with realistic premises, logical causality, and empirical backing. Second, the strategy must be chosen through an open, deliberative process. It requires that multiple options be placed on the table, that objections and counterarguments be examined without being suppressed, and that a responsible decision be made in the end.

By adopting these two conditions, the focus of rationality shifts from whether it hit the mark or missed, to how it was thought out and decided. This is important. In international politics, no matter how carefully one thinks, results are swayed by external factors such as the reactions of other countries, the unity of allies, and shifts in domestic public opinion. Linking rationality too closely to results oversimplifies decision-making in a complex world.

3. A World of Uncertainty and the Theory-Based Image of a Nation: The characteristic of international politics is uncertainty. In a certain world, necessary information is available, and one knows what will happen if a certain policy is chosen. In a world of risk, even if the results are unknown, probabilities can be estimated if there is sufficient data. However, in a world of uncertainty, the reality is that necessary information is lacking from the start, and it is difficult to establish reliable probabilities. Military strength, the intentions of the other side, the prolongation of war, and the burden of occupation governance cannot be accurately measured in advance.

In this environment, a framework that explains and organizes reality is more necessary than detailed calculations. This is where theory becomes important. Theory organizes limited information into a meaningful form and indicates what should be prioritized and which causal relationships should be guarded against. Policy makers interpret the situation with the theories at hand and construct policies, much like scientists formulate hypotheses and verify them in reality. Of course, theories are not omnipotent, but they are indispensable for setting a direction in a sea of fragmented information.

4. The Role of Deliberation and Organizational Dynamics That Destroy Rationality: In the theory-based view, policy makers use an explanatory framework to understand the world and use it as a clue to connect goals and means. This is an idea that views leaders as people who think using theory. However, even if an individual has a theory, collective decision-making is essential for it to take shape as policy. Deliberation is a mechanism for comparing different theories and policy proposals, examining which assumptions are valid, and which side effects are significant. If deliberation functions, errors and overconfidence are pointed out at an early stage, and it becomes easier for premises to be revised if necessary.

On the other hand, deliberation does not arise naturally. When the enforcement of silence, concealment of information, and exclusion of criticism occur, even if theory is spoken of on the surface, rationality as a process is impaired. The result changes significantly depending on whether the person at the top of the decision-making group acts as a coordinator who encourages discussion or plays a dominant role in imposing their own view. In the former, objections emerge and examination deepens, but in the latter, opposing opinions are intimidated, and the scrutiny of theory is likely to stop.

5. Bounded Rationality: Heuristics and Analogies

As political psychology points out, humans do not possess perfect information processing capabilities. When time or information is scarce, people tend to use shortcut thinking called heuristics. While useful in daily life, this can be dangerous in complex international crises. A representative example is the analogy of applying past successful experiences to the present. Under crisis, rather than reading the long game, one might fixate on a move that worked before.

Furthermore, heuristics include tendencies such as being swayed by easily noticeable information, over-applying past patterns, and having initial impressions fixate one's judgment. While these help in quickly understanding complex situations, they also lead to oversights and misunderstandings.

Additionally, groupthink can occur within organizations. When the atmosphere of wanting to avoid conflict or the pressure to align with a superior's intentions becomes strong, it becomes difficult for opposing opinions to emerge. In a democracy, the plurality of the parliament, media, and bureaucracy can act as a check, but it is pointed out that as crises deepen, these checks become less effective. Therefore, it is necessary not only to speak of rationality as a system or ideal but also to verify how open the actual decision-making process was.

6. Caution Regarding Computational Rationality: The Ideal of Expected Utility

There is also a view that equates rationality with optimization calculations. This is the idea of assigning values and probabilities to the results of each option and choosing the action that maximizes the expected value. However, in international politics, it is difficult to even exhaustively list the results of options, and probabilities cannot be assigned. Even if it can be held up as an ideal, it is not a method that can be applied directly in the field. If one equates rationality with this calculation, it is easy to conclude that real-world policymakers are always inadequate, leading to a binary of whether discussion is possible or not. In this paper, rather than the perfection of calculation, we consider dealing with uncertainty through reliable explanatory frameworks and deliberation to be a more realistic form of rationality.

7. Case Studies

7.1 Pearl Harbor: Procedural Rationality and the Collapse of Results

The attack on Pearl Harbor is often considered reckless by later generations, but if one reconstructs the logic of the leaders at the time, a certain path becomes visible. There was a need to advance into Southeast Asia to secure resources. However, that would invite conflict with the United States. Therefore, the fleet should launch a surprise attack before the U.S. could establish a total war system, leading to a short-term decisive battle and negotiations. It is possible to understand this as a strategy based on a chain of causality that was repeatedly examined among those involved. Although it ended in a major failure as a result, it can be evaluated as having approached the conditions of rationality because it took the form of theory and discussion as a process.
However, at the same time, the possibility remains that the analogy of past success narrowed the examination of options. If the success of past surprise attacks caused them to underestimate factors such as the opponent's production capacity, alliance system, and the consequences of a long-term war, then the reliability of the theory and the quality of the deliberation were compromised. This case shows that rationality and irrationality can coexist within the same process.

7.2 The Munich Analogy: When Lessons Bind Thinking

A typical example of an analogy under crisis is the lesson that appeasement always invites war. When one attempts to compromise in diplomatic negotiations, criticism erupts by overlaying it with past failures, and the examination of other options may stop. Here, past events become tools to decide the conclusion in advance rather than clues for thinking.
Of course, attempting to generalize lessons is not necessarily a mistake in itself. The problem lies in ending the discussion with only symbolic words without carefully checking which conditions are the same as at that time and which are different. If analogies are abused as a substitute for theory, deliberation becomes formalized, and the foundation of rationality weakens.

7.3 The 2003 Iraq Invasion: Organizational Processes That Create Irrationality

In contrast, the 2003 Iraq invasion can be understood as an example where low-reliability theory and non-deliberative processes overlapped. Policy authorities relied heavily on the prospect that democratization would solve regional security problems and the premise that stability could be maintained after occupation with a small force. However, experts and some military officials repeatedly pointed out the difficulties of occupation governance and the size of the necessary forces. Even so, criticism was not sufficiently taken into account, and the examination of post-war planning was postponed.

Furthermore, movements to neutralize opposing opinions arose within the organization, and decision-making was effectively fixed. When actions such as ignoring criticism, avoiding discussion, suppressing opposition, and forcing conformity through pressure overlap, the core of rationality—verifying hypotheses and updating premises—does not function. What is important here is not to say it was irrational because it failed, but that one can confirm procedural defects such as the fact that discussion was not open in the stages leading up to the failure and that the realism of the theory was not sufficiently scrutinized.

8. Comprehensive Discussion: Rationality as a Principle, Irrationality as a Constant Risk

From the above, the rationality of a nation must be grasped in a dual sense. One is that since a nation is placed in a world where it must fight for survival, it has a strong motivation to seek the best policy based on theory. This motivation pushes policymakers away from shortcut thinking and toward emphasizing evidence and explanation. The other is that even so, as long as the subjects of decision-making are humans and organizations, the room for shortcut thinking and groupthink to enter cannot disappear.

Therefore, it cannot be simply said that a nation is always rational or often irrational. The key is in which phase, to what extent, a reliable theory was used, and to what extent deliberation was protected. The observation that the higher the pressure of a crisis, the more likely the closing of discussion and jumping to analogies occur, indicates the importance of mechanisms that institutionally support rationality.

Also, for the position of analyzing a nation from the outside, this framework is useful. Even if the opponent's actions are morally unacceptable, if one can estimate based on what theory and through what deliberative process they were chosen, it becomes easier to predict the next move. Conversely, if internal deliberation is broken, actions suddenly become difficult to read. The evaluation of rationality is also a tool for understanding and prediction.

9. Conclusion

This paper grasped the rationality of a nation as a process rather than a result and organized it based on two conditions: reliable theory and deliberation. Based on this, we confirmed that under bounded rationality, heuristics, analogies, and groupthink can distort decision-making. The Pearl Harbor attack can be understood as an example that possessed a certain degree of rationality as a process but collapsed due to a misreading of the environment. The lessons of Munich can help deliberation depending on how they are used, but they can also become a curse that binds discussion. The Iraq invasion is positioned as an example where irrationality expanded because both the reliability of the theory and deliberation were damaged.

Future tasks lie in how to create an environment where the decision-making process can be inspected and where the verification and updating of hypotheses work, rather than condemning specific policies. Nations try to act rationally, but whether that effort actually bears fruit depends on the quality of the theory, the system of deliberation, and a culture that allows for dissent even under crisis.