FREDERICKSBURG, Va. — Kat Renfroe was at Mass when she saw a volunteer opportunity in the bulletin. Her Catholic parish was looking for tutors for Afghan youth, newly arrived in the United States. There was a personal connection for Renfroe. Her husband, now retired from the Marine Corps, had deployed to Afghanistan four times. “He just never talked about any other region the way he did about the people there,” she said. She signed up to volunteer. “It changed my life,” she said. That was seven