When Lance Cpl. Ruben Valdez Jr. returned to his hometown last fall to marry a childhood playmate, the residents of San Diego, Texas, gave him a parade, cheering him as he rode in the back of a convertible. "He was always behaved, had a lot of friends, just a pleasant boy to be around," said Luis Pizzini, the principal of San Diego High School, where Valdez graduated in 2001. He remembered the Marine as a "respectful young man" and "an excellent son." The 21-year-old was killed April 17 in a hostile attack in Iraq's Anbar province. He was stationed at Twentynine Palms, Calif. School secretary Connie Perez remembered how, as a first-grader, Valdez was too shy to step off the school bus unless she held his hand. "Ruben was just a sweet,...