Suddenly the enemy that Blue Team thought could be read like an open book was a bit more mysterious. What was Red Team doing? Van Riper was supposed to be cowed and overwhelmed in the face of a larger foe. But he was too much of a gunslinger for that. On the second day of the war, he put a fleet of small boats in the Persian Gulf to track the ships of the invading Blue Team navy. Then, without warning, he bombarded them in an hour-long assault with a fusillade of cruise missiles. When Red Team’s surprise attack was over, sixteen American ships lay at the bottom of the Persian Gulf. Had Millennium Challenge been a real war instead of just an exercise, twenty thousand American servicemen and women would have been killed before their own army had even fired a shot.

“As the Red force commander, I’m sitting there and I realize that Blue Team had said that they were going to adopt a strategy of preemption,” Van Riper says. “So I struck first. We’d done all the calculations on how many cruise missiles their ships could handle, so we simply launched more than that, from many different directions, from offshore and onshore, from air, from sea. We probably got half of their ships. We picked the ones we wanted. The aircraft carrier. The biggest cruisers. There were six amphibious ships. We knocked out five of them.”

In the weeks and months that followed, there were numerous explanations from the analysts at JFCOM about exactly what happened that day in July. Some would say that it was an artifact of the particular way war games are run. Others would say that in real life, the ships would never have been as vulnerable as they were in the game. But none of the explanations change the fact that Blue Team suffered a catastrophic failure. The rogue commander did what rogue commanders do. He fought back, yet somehow this fact caught Blue Team by surprise. In a way, it was a lot like the kind of failure suffered by the Getty when it came to evaluating the kouros: they had conducted a thoroughly rational and rigorous analysis that covered every conceivable contingency, yet that analysis somehow missed a truth that should have been picked up instinctively. In that moment in the Gulf, Red Team’s powers of rapid cognition were intact—and Blue Team’s were not. How did that happen?

One Saturday evening not long ago, an improvisation comedy group called Mother took the stage in a small theater in the basement of a supermarket on Manhattan’s West Side. It was a snowy evening just after Thanksgiving, but the room was full. There are eight people in Mother, three women and five men, all in their twenties and thirties. The stage was bare except for a half dozen white folding chairs. Mother was going to perform what is known in the improve world as a Harold. They would get up onstage, without any idea whatsoever of what character they would be playing or what plot they would be acting out, take a random suggestion from the audience, and then, without so much as a moment’s consultation, make up a thirty-minute play from scratch.

One of the group members called out to the audience for a suggestion. “Robots,” someone yelled back. In improv, the suggestion is rarely taken literally, and in this case, Jessica, the actress who began the action, said later that the thing that came to mind when she heard the word “robots” was emotional detachment and the way technology affects relationships. So, right then and there, she walked onstage, pretending to read a bill from the cable television company. There was one other person onstage with her, a man seated in a chair with his back to her. They began to talk. Did he know what character he was playing at that moment? Not at all; nor did she or anyone in the audience. But somehow it emerged that she was the wife, and the man was her husband, and she had found charges on the cable bill for porn movies and was distraught. He, in turn, responded by blaming their teenaged son, and after a spirited back-and-forth, two more actors rushed onstage, playing two different characters in the same narrative. One was a psychiatrist helping the family with their crisis. In another scene, an actor angrily slumped in a chair. “I’m doing time for a crime I didn’t commit,” the actor said. He was the couple’s son. At no time as the narrative unfolded did anyone stumble or freeze or look lost. The action proceeded as smoothly as if the actors had rehearsed for days. Sometimes what was said and done didn’t quite work. But often it was profoundly hilarious, and the audience howled with delight. And at every point it was riveting: here was a group of eight people up on a stage without a net, creating a play before our eyes.

Improvisation comedy is a wonderful example of the kind of thinking that Blink is about. It involves people making very sophisticated decisions on the spur of the moment, without the benefit of any kind of script or plot. That’s what makes it so compelling and—to be frank—terrifying. If I were to ask you to perform in a play that I’d written, before a live audience with a month of rehearsal, I suspect that most of you would say no. What if you got stage fright? What if you forgot your lines? What if the audience booed? But at least a conventional play has structure. Every word and movement has been scripted. Every performer gets to rehearse. There’s a director in charge, telling everyone what to do. Now suppose that I were to ask you to perform again before a live audience—only this time without a script, without any clue as to what part you were playing or what you were supposed to say, and with the added requirement that you were expected to be funny. I’m quite sure you’d rather walk on hot coals. What is terrifying about improv is the fact that it appears utterly random and chaotic. It seems as though you have to get up onstage and make everything up, right there on the spot.

But the truth is that improv isn’t random and chaotic at all. If you were to sit down with the cast of Mother, for instance, and talk to them at length, you’d quickly find out that they aren’t all the sort of zany, impulsive, free-spirited comedians that you might imagine them to be. Some are quite serious, even nerdy. Every week they get together for a lengthy rehearsal. After each show they gather backstage and critique each other’s performance soberly. Why do they practice so much? Because improv is an art form governed by a series of rules, and they want to make sure that when they’re up onstage, everyone abides by those rules. “We think of what we’re doing as a lot like basketball,” one of the Mother players said, and that’s an apt analogy. Basketball is an intricate, high-speed game filled with split-second, spontaneous decisions. But that spontaneity is possible only when everyone first engages in hours of highly repetitive and structured practice—perfecting their shooting, dribbling, and passing and running plays over and over again—and agrees to play a carefully defined role on the court. This is the critical lesson of improv, too, and it is also a key to understanding the puzzle of Millennium Challenge: spontaneity isn’t random. Paul Van Riper’s Red Team did not come out on top in that moment in the Gulf because they were smarter or luckier at that moment than their counterparts over at Blue Team. How good people’s decisions are under the fast-moving, high-stress conditions of rapid cognition is a function of training and rules and rehearsal.

One of the most important of the rules that make improv possible, for example, is the idea of agreement, the notion that a very simple way to create a story—or humor—is to have characters accept everything that happens to them. As Keith Johnstone, one of the founders of improv theater, writes: “If you’ll stop reading for a moment and think of something you wouldn’t want to happen to you, or to someone you love, then you’ll have thought of something worth staging or filming. We don’t want to walk into a restaurant and be hit in the face by a custard pie, and we don’t want to suddenly glimpse Granny’s wheelchair racing towards the edge of a cliff, but we’ll pay money to attend enactments of such events. In life, most of us are highly skilled at suppressing action. All the improvisation teacher has to do is to reverse this skill and he creates very ‘gifted’ improvisers. Bad improvisers block action, often with a high degree of skill. Good improvisers develop action.”