Arizona Struggles To Patrol Vast Border With Mexico

YUMA, AZ - MARCH 16: Men run after crossing illegally into the U.S. from Mexico on March 16, 2006 at the border town of near San Luis, south of Yuma, Arizona. As Congress begins a new battle over immigration policy, U.S. Customs and Border Protection (CBP) border patrol agents in Arizona are struggling to control undocumented immigrants that were pushed into the region by the 1990's border crack-down in California called Operation Gatekeeper. A recent study by the Pew Hispanic Center, using Census Bureau data, estimates that the U.S. currently has an illegal immigrant population of 11.5 million to 12 million, about one-third of them arriving within the past 10 years. More than half are reportedly from Mexico. Ironically, beefed-up border patrols and increased security are reportedly having the unintended result of deterring many from returning to their country of origin. (Photo by David McNew/Getty Images)