Gen. James Mattis thinks about when, and how, American troops should put their lives at risk.

Officers need that connection with their troops because counterinsurgency's call for increased risk undermines the relationship between officers and the men they lead. The younger officers don't think the generals understand what it's like to walk the streets not knowing who is trying to kill you and who isn't. "You have to find a way to put it to them so that they don't think you're some fat cat general saying 'hey risk yourself and put the women and children first and the enemy gets a bye,' " says Mattis.

The second fundamental necessity for counterinsurgency is ferocity. It is a paradox: To be restrained, you must be willing to be ferocious. Ferocity gives soldiers and Marines the confidence to accept more risk. If soldiers are certain they can be ferocious when the time comes, it will make them less jumpy when they are accepting the increased personal risks of leaving a protected base to engage with the locals or dropping body armor while they walk through town. Ferocity makes a unit feel more comfortable knowing they can fight their way out of a situation if necessary.

 "We have an overweening sensitivity to the slaughtering of our enemies," says Mattis. "I've put medals on Marines who have killed guys at 700 yards. And I've come right out and said it: 'That was a beautiful shot.' You must reward the kind of behavior that you want." This sentiment got Mattis into trouble in 2005 when he said, in some cases it was "fun to shoot some people." He has also been battered by public sensitivity over his handling of the 2005 killing of 24 Iraqis in Haditha. Liberals think he was too soft on the Marines involved. Conservatives think he bowed to political pressure and was too harsh on them.

Maintaining this culture of ferocity is why Mattis bristles about excessive hand-wringing over Marines who might want to ride without motorcycle helmets. Marines need to be risk-takers. That's why the corps advertises at extreme sporting events. Ferocity is part of what the corps works to build in boot camp, and it is central to its storied history and traditions. If that's the kind of spirit you need to fight wars, then you have to accept that the kind of person you want is going to sometimes ride at 120 miles an hour on a bike and hurt himself. "It's not that I'm trying to extol this kind of behavior," says Mattis, "but you have to have people who know that risk-taking sometimes means that people are going to get hurt. If you can't accept that, if your view of warfare is always hurtful and you're psychologically damaged by it, you start putting up guardrails."

It might be easy to think Mattis is cavalier about the risks he asks his men to take. That was the charge when he relieved a colonel on the march into Baghdad who he thought was taking too few risks. In conversation he, like other Marines and soldiers, speaks about killing and death as civilians might talk about the weather. But he is not cavalier. He is obsessed with using simulators to train troops because he wants to reduce stupid deadly mistakes. It's also why he is brutal about academics "who have never had to write a letter to the family of a dead Marine" and military planners who forget that it is 18-year-olds who will have to take the risks at the other end of their grand theories.

When asked to single out the thing that makes him risk averse, Mattis cites casualties. At times he has asked Navy doctors to assemble a field hospital from scratch while his battalion watches to reassure the troops they will get treated immediately if they get wounded. But Mattis asks his subordinates not to report casualties in the midst of battle.

Mattis believes in his mission and that freedom is at stake in the wars America fights. If it is his mission to engage in the fight, he has to know when to put death aside or it will keep him from doing his job. He won't be able to take the risks he thinks are necessary to win, or the risks that might keep even more Marines from dying tomorrow.

Read the other profiles in this series, on  rock climbers Eli Simon and Pete Fasoldt, entrepreneurs Redbeacon, the band Girlyman,  and Marine Gen. James Mattis.

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