NOGALES, AZ - JUNE 22: U.S. Army National Guardsmen scan the U.S.-Mexico border with a thermal imaging camera at dusk on June 22, 2011 in Nogales, Arizona. The Pentagon recently extended the ... more 
NOGALES, AZ - JUNE 22: U.S. Army National Guardsmen scan the U.S.-Mexico border with a thermal imaging camera at dusk on June 22, 2011 in Nogales, Arizona. The Pentagon recently extended the deployment of some 1,200 guardsmen who were deployed last year to assist with border security on the U.S.-Mexico border until September 30. Soldiers at Early Identification Team (EIT) observation posts in Nogales work 24 hour shifts, each taking turns resting for 4 hours during the night. The National Guard troops are strictly on surveillance duty, although they are armed and have been credited with helping U.S. Border Patrol agents arrest up to 17,000 illegal immigrants crossing into the United States. (Photo by John Moore/Getty Images) less 
1 / 7
Getty Images | Photo By John Moore / Getty Images
Thu, Jun 23, 2011 10:07 AM EDT