Army Reservist James E. Dean had already served 18 months in Afghanistan when he was notified three weeks ago that he would be deployed to Iraq later this month. The prospect of returning to war sent the St. Mary's County resident into a spiral of depression, a neighbor said. Despondent about his orders, Dean barricaded himself inside his father's home with several weapons on Christmas, threatening to kill himself. After a 14-hour standoff with authorities, Dean was killed yesterday by a police officer after he aimed a gun at another officer, police said. Wanda Matthews, who lives next door to...