Arizona National Guard Assist U.S. Border Patrol To Monitor Vast Border With Mexico

NOGALES, AZ - DECEMBER 07: Arizona National Guardsmen watch over the U.S. border with Mexico at an observation post on December 7, 2010 in Nogales, Arizona. The Obama administration ordered more than 500 soldiers placed along the Arizona border to man "entry identification sites" and spot illegal immigrants crossing into the United States. The troops, who have no detention authority, radio U.S. Border Patrol agents when they spot immigrants crossing. The troop deployment was meant to further bolster border security and help stem illegal immigration into Arizona, which has become a flashpoint for the issue nationwide. (Photo by John Moore/Getty Images)