It was only a virtual Baghdad, baking under a virtual sun. As in real life, though, troops were dodging gunfire. I was at the Institute for Creative Technologies in Marina Del Rey, Calif., playing a new X box video game called Full Spectrum Warrior. Leading eight men in an Army squad on a patrol of the war-torn city, I got a taste, however approximate, of why Iraq is such a hard place to be a soldier these days. My job, as squad leader, was to order my soldiers where to go and what to do. First, I sent half of...