They had slogged through knee-deep mud carrying 100 pounds of gear, fingers glued to the triggers of their M-4 carbines, all the while on the lookout for insurgents. Now, after five near-sleepless nights, trying to avoid hypothermia in freezing temperatures, the grunts of the 1st Battalion of the 6th Marine Regiment finally had a moment to relax. As the sun set Thursday evening over the rubbled market where they set up camp, four of them sat around an overturned blue bucket and began playing cards. A few cracked open dog-eared paperbacks. Some heated their rations-in-a-bag, savoring their first warm dinner...