FORT BLISS, Tex. — When Joseph K. Goodwin graduated from Harvard in the spring of 2001, his ideas about where he was going did not include war. But early in February, Lieutenant Goodwin ascended the stage at the Army's Air Defense Artillery School graduation ceremony here, recognized as one of two distinguished honor graduates in his 120-member class, picked by his commanders as among the best to lead his fellow soldiers in battle. Standing next to a fleet of armored vehicles used to fire short-range Stinger missiles, which he could soon be called to operate in a conflict with Iraq,...