RIO GRANDE CITY, TX - AUGUST 05:  Children walk across a railroad bridge August 5, 2008 in Rio Grande City, Starr County,Texas, along the border with Mexico. By many social indicators, Starr County is the poorest county in the United States. Few of its residents have full health or dental insurance and many of them must travel across the border to Mexico in order to get medical attention and buy medicine. The two-week Operation Lone Star, run by the Texas armed forces and state health officials, provided free medical care to more than 10,000 people in areas along the Texas-Mexico border.  (Photo by John Moore/Getty Images)
{}