Spoiler: positive expected utility. That's what it's good for.

In The War Trap[1], Bruce Bueno de Mesquita lays out a theory of war that beats all other theories. This is a great example of a model that is parsimonious, wrong, and useful. For every assumption Bueno de Mesquita makes, the reader goes, “What? That's not how things work.”

Yet when we measure the things Bueno de Mesquita asks us to measure, and apply the equations he lays out, the result ends up closely matching reality. What's better, his equations arrive at the same results that previous ad hoc theories did – and also explains observations those theories could not account for.

The work Bueno de Mesquita did on The War Trap is creative, intelligent, and inspiring.

We don’t know what a potential war will be like

Here's the scene for the book: there's an active international dispute, and one country has issued a threat of solving it with violence. We are faced with the same questions that troubled Tolstoy when he wrote War and Peace:

Will the threat escalate into a full-on war?
If so, which countries will join the war?
How bloody will the war be?

Tolstoy's [...]

---

Outline:

(00:57) We don't know what a potential war will be like

(02:05) We measure military alliances and fuel usage

(03:52) Then we compute expected utilities

(06:20) Predictions from expected utility calculus

(08:25) The surprising effects of good relations

(10:08) Predicting the severity of wars

(12:31) It's impossible until the right person tries

The original text contained 9 footnotes which were omitted from this narration.

---

First published:
July 20th, 2026

Source:
https://www.lesswrong.com/posts/qnDvrbNz5eteax3cN/war-what-is-it-good-for

---

Narrated by TYPE III AUDIO.

“War – What is it Good For?” by kqr

LessWrong (30+ Karma)

“War – What is it Good For?” by kqr