With Millennium Challenge, then, Blue Team was given greater intellectual resources than perhaps any army in history. JFCOM devised something called the Operational Net Assessment, which was a formal decision-making tool that broke the enemy down into a series of systems—military, economic, social, political—and created a matrix showing how all those systems were interrelated and which of the links among the systems were the most vulnerable. Blue Team’s commanders were also given a tool called Effects-Based Operations, which directed them to think beyond the conventional military method of targeting and destroying an adversary’s military assets. They were given a comprehensive, real-time map of the combat situation called the Common Relevant Operational Picture (CROP). They were given a tool for joint interactive planning. They were given an unprecedented amount of information and intelligence from every corner of the U.S. government and a methodology that was logical and systematic and rational and rigorous. They had every toy in the Pentagon’s arsenal.

“We looked at the full array of what we could do to affect our adversary’s environment—political, military, economic, societal, cultural, institutional. All those things we looked at very comprehensively,” the commander of JFCOM, General William F. Kernan, told reporters in a Pentagon press briefing after the war game was over. “There are things that the agencies have right now that can interrupt people’s capabilities. There are things that you can do to disrupt their ability to communicate, to provide power to their people, to influence their national will . . . to take out power grids.” Two centuries ago, Napoleon wrote that “a general never knows anything with certainty, never sees his enemy clearly, and never knows positively where he is.” War was shrouded in fog. The point of Millennium Challenge was to show that, with the full benefit of high-powered satellites and sensors and supercomputers, that fog could be lifted.

This is why, in many ways, the choice of Paul Van Riper to head the opposing Red Team was so inspired, because if Van Riper stood for anything, it was the antithesis of that position. Van Riper didn’t believe you could lift the fog of war. His library on the second floor of his house in Virginia is lined with rows upon rows of works on complexity theory and military strategy. From his own experiences in Vietnam and his reading of the German military theorist Carl von Clausewitz, Van Riper became convinced that war was inherently unpredictable and messy and nonlinear. In the 1980s, Van Riper would often take part in training exercises, and, according to military doctrine, he would be required to perform versions of the kind of analytical, systematic decision making that JFCOM was testing in Millennium Challenge. He hated it. It took far too long. “I remember once,” he says, “we were in the middle of the exercise. The division commander said, ‘Stop. Let’s see where the enemy is.’ We’d been at it for eight or nine hours, and they were already behind us. The thing we were planning for had changed.” It wasn’t that Van Riper hated all rational analysis. It’s that he thought it was inappropriate in the midst of battle, where the uncertainties of war and the pressures of time made it impossible to compare options carefully and calmly.

In the early 1990s, when Van Riper was head of the Marine Corps University at Quantico, Virginia, he became friendly with a man named Gary Klein. Klein ran a consulting firm in Ohio and wrote a book called Sources of Power, which is one of the classic works on decision making. Klein studied nurses, intensive care units, firefighters, and other people who make decisions under pressure, and one of his conclusions is that when experts make decisions, they don’t logically and systematically compare all available options. That is the way people are taught to make decisions, but in real life it is much too slow. Klein’s nurses and firefighters would size up a situation almost immediately and act, drawing on experience and intuition and a kind of rough mental simulation. To Van Riper, that seemed to describe much more accurately how people make decisions on the battlefield.

Once, out of curiosity, Van Riper and Klein and a group of about a dozen Marine Corps generals flew to the Mercantile Exchange in New York to visit the trading floor. Van Riper thought to himself, I’ve never seen this sort of pandemonium except in a military command post in war—we can learn something from this. After the bell rang at the end of the day, the generals went onto the floor and played trading games. Then they took a group of traders from Wall Street across New York Harbor to the military base on Governor’s Island and played war games on computers. The traders did brilliantly. The war games required them to make decisive, rapid-fire decisions under conditions of high pressure and with limited information, which is, of course, what they did all day at work. Van Riper then took the traders down to Quantico, put them in tanks, and took them on a live fire exercise. To Van Riper, it seemed clearer and clearer that these “overweight, unkempt, long-haired” guys and the Marine Corps brass were fundamentally engaged in the same business—the only difference being that one group bet on money and the other bet on lives. “I remember the first time the traders met the generals,” Gary Klein says. “It was at the cocktail party, and I saw something that really startled me. You had all these marines, these two- and three-star generals, and you know what a Marine Corps general is like. Some of them had never been to New York. Then there were all these traders, these brash, young New Yorkers in their twenties and thirties, and I looked at the room and there were groups of two and three, and there was not a single group that did not include members of both sides. They weren’t just being polite. They were animatedly talking to each other. They were comparing notes and connecting. I said to myself, These guys are soul mates. They were treating each other with total respect.”

Millennium Challenge, in other words, was not just a battle between two armies. It was a battle between two perfectly opposed military philosophies. Blue Team had their databases and matrixes and methodologies for systematically understanding the intentions and capabilities of the enemy. Red Team was commanded by a man who looked at a long-haired, unkempt, seat-of-the pants commodities trader yelling and pushing and making a thousand instant decisions an hour and saw in him a soul mate.

On the opening day of the war game, Blue Team poured tens of thousands of troops into the Persian Gulf. They parked an aircraft carrier battle group just offshore of Red Team’s home country. There, with the full weight of its military power in evidence, Blue Team issued an eight-point ultimatum to Van Riper, the eighth point being the demand to surrender. They acted with utter confidence, because their Operational Net Assessment matrixes told them where Red Team’s vulnerabilities were, what Red Team’s next move was likely to be, and what Red Team’s range of options was. But Paul Van Riper did not behave as the computers predicted.

Blue Team knocked out his microwave towers and cut his fiber-optics lines on the assumption that Red Team would now have to use satellite communications and cell phones and they could monitor his communications.

“They said that Red Team would be surprised by that,” Van Riper remembers. “Surprised? Any moderately informed person would know enough not to count on those technologies. That’s a Blue Team mind-set. Who would use cell phones and satellites after what happened to Osama bin Laden in Afghanistan? We communicated with couriers on motorcycles, and messages hidden inside prayers. They said, ‘How did you get your airplanes off the airfield without the normal chatter between pilots and the tower?’ I said, ‘Does anyone remember World War Two? We’ll use lighting systems.’”