Trump’s Madman Strategy

And What It Says About the New Nature of International Politics

Game theorists and foreign policy analysts have known for long that it sometimes pays off to make others believe that you’re irrational or even “mad.” To understand why, consider the general structure of what can be called the Commitment Problem:

(i) You would want (because this is in your interest) that Other does X.

(ii) Other will do X only if she believes that you will do Y in case she does X (or non-X).

(iii) You promise (or threaten) Other that you will do Y if she does (or doesn’t) X.

(iv) However, if she were to do (or not do) X, it would not be rational for you to do Y.

The Commitment Problem arises in particular in the context of noncredible promises or threats. You promise or make a threat to induce someone else to behave in a certain way but, very often, keeping your promise or carrying the threat is not in your interest. If your partner/opponent knows this, then your promise/threat is useless and has no effect. However, if you can convince your partner/opponent that you will keep your promise or carry the threat anyway, then promising or threatening becomes strategically useful. There are two general ways to do that. First, you can make your partner/opponent believe that if she does (does not) X, then you will automatically do Y. This can either be because you have automatized the decision-making process (as with the Doomsday machine) or because you’ve voluntarily and publicly reduced your option to only one, e.g., burning the bridge needed for an eventual retreat of your troops.[1]

The other approach is to convince the partner/opponent that you may not act rationally if she were to do X. In many cases, this is unlikely to work. The reason is that we tend, for evolutionary and cultural reasons, to engage other persons as rational agents whose behavior can be accounted for in rational terms. When we observe a behavior, our prima facie assumption is that there are “good reasons” that explain this behavior. These reasons are typically formulated in intentional states such as a desire or a belief. If I see you standing up from the sofa and going to the fridge, I’ll for instance assume that you (in the context) want a beer. If I see you suddenly running, I will assume you believe there is an imminent danger.[2] The point is that we use the rationality assumption as a loose and broad principle to ascribe intentional states to others. From everyday experience to mathematical social sciences, this is the way we make sense of others’ behavior.

If you create a doomsday machine or burn the bridge that could permit your troops to retreat, you literally create a commitment, you’re getting committed. Things are different in the second approach. Here, you want to convince others that you’re a committed person, i.e., that you’ve traits that make you the kind of person to act irrationally in a specific kind of situation. Thomas Schelling has a nice discussion of what is to be a committed person in his essay “Strategies of Commitment”:

“In Joseph Conrad’s Secret Agent, anarchists plot to destroy Greenwich Observatory. They get their nitroglycerin from “the professor,” a stunted little chemist. The authorities know who provides the stuff, but this little chemist walks the streets of London with immunity. A young man tied in with the Greenwich job is in wonderment: why, he asks, do the police not apprehend him? The “professor” answers that the police may not shoot him from a safe distance, for that would be a denial of the “bourgeois morality” that the anarchists want to discredit. And they dare not capture him physically because he always keeps some of the “stuff” on his person. He keeps his right hand in his trouser pocket holding a hollow ball at the end of a tube that reaches a container of nitroglycerin in his jacket. All he has to do is to press that little ball and anybody near will be blown to bits. The young man wonders why the police would ever believe anything so preposterous as that the “professor” would actually blow himself up. The stunted chemist's explanation is calm. “In the last instance, it is character alone that makes for one’s safety… I have the means to make myself deadly, but that by itself, you understand, is absolutely nothing in the way of protection. What is effective is the belief those people have in my will to use the means. That’s their impression. It is absolute. Therefore I am deadly.”

In this case, commitment is built in the character of one’s personae, a character that one has to make sure everybody else knows about. In foreign policy, this insight is captured in the so-called “madman theory.” In substance, it says that making oneself unpredictable is an effective way to have leaders concede to your threats. The best way to be unpredictable is to appear crazy, i.e., to make your acts impossible to account in terms of desires and beliefs that we could ascribe to any reasonable person. There is a long list of international leaders that, more or less systematically, have tried to implement the madman theory. Donald Trump is arguably the most recent name on this list.[3]

Cole Thomas, “The Course of Empire: Destruction” (1836)

Trump is an interesting case, for at least two reasons. First, on this list, he’s among the few ones (maybe with Richard Nixon) who have been leading a democratic country. Indeed, among the madmen in foreign policy, we would rather think of autocrats like Putin, Kim Jong Un, or Khrushchev. This fact alone is disturbing. That autocrats are crazy, or at least likely to be, is after all not a surprise. There is nothing in an autocratic regime that prevents a madman from rising to the top – craziness may actually be a real asset. Democratic institutions should in theory prevent that from happening. The very fact that one is the leader of a democratic regime should decrease the likelihood that one is genuinely mad. So, two possibilities. Either Trump’s madman strategy is misguided and is unlikely to work, or the fact that he can effectively use this strategy says a lot about the state of democracy in the U.S. and how it is viewed by foreign leaders.

Second, Trump’s madman strategy is not restricted to foreign policy strictly speaking. I think a good case can be made for the claim that his jaw-dropping tariff policies are also part of a more general attempt to appear completely unpredictable and, yes, irrational. Nobody, except for the millions of (pardon me for the term) “Trumproids” who blindly endorse him, see any economic merit in these policies. The only explanation is that Trump wants to genuinely appear to be mad to gain leverage over other international leaders. Or maybe he is genuinely mad.

The problem with madman strategies is that they are double-edged swords. If they work, they increase your threat capacities, but they also undermine your ability to commit to respect agreements. Attentive readers will have noted that the Commitment Problem is both about promises and threats. What you eventually gain on the latter you lose on the former. This is a real problem if you intend to act within a rule-based order, i.e., a political order where behavior follows widely accepted rules and where all actors accept these rules as constraints and reasons for action. A rule-based order is possible only if everybody abides by the rules and, even more importantly, believes that everybody else will also abide. A major post-WWII achievement has been the establishment of such an order at the international level, where relations between countries are regulated by treaties. Madman strategies can only undermine the international rule-based order.

This may actually be Trump’s ultimate objective.[4] Trump and those libertarians who support him share a radically illiberal conception of politics where sovereignty is ultimately located in the person – not the rules and the institutions – who has the effective ability to decide when the rules apply or not. As the German legal scholar and notorious critic of liberalism Carl Schmitt put it, “[s]overeign is he who decides on the exception.”[5] I noted above that few democratic leaders have historically adopted a madman strategy. This is not a coincidence. More than its immediate consequences, we should be worried about what Trump’s madman strategy says about the undergoing change of nature of politics in the U.S. and the world.

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[1] Jon Elster calls these “precommitment strategies.” See for instance Jon Elster, Ulysses Unbound: Studies in Rationality, Precommitment, and Constraints (Cambridge University Press, 2000). The commitment problem is largely discussed by Thomas Schelling, especially Thomas C. Schelling, The Strategy of Conflict (Harvard University Press, 1981).

[2] I’m here loosely following Daniel Dennett’s instance stance theory. Daniel C. Dennett, The Intentional Stance (MIT Press, 1989).

[3] See Roseanne McManus, “The Limits of the Madman Theory,” Foreign Affairs, January 24, 2025, https://www.foreignaffairs.com/united-states/limits-madman-theory.

[4] “Like It or Not, the Rules-Based Order Is No More,” POLITICO, February 5, 2025, https://www.politico.eu/article/rules-danish-prime-minister-mette-frederiksen-us-president-donald-trump-greenland-power-politics/.

[5] Carl Schmitt, Political Theology: Four Chapters on the Concept of Sovereignty, trans. George Schwab, 1st edition (Chicago: University of Chicago Press, 1922 [2006]).