7/6/2011 - Service members re-enlist under Army Gen. David H. Petraeus's reading at Kandahar Air Field, Afghanistan, July 4, 2011. General Petraeus is the senior commander of U.S. and coalition forces in Afghanistan. (U.S. Air Force photo by Senior Airman Corey Hook)

7/6/2011 - Army Gen. David H. Petraeus, senior commander of U.S. and coalition forces in Afghanistan, greets 235 service members after they re-enlisted under his reading at Kandahar Air Field, Afghanistan, July 4, 2011. This year, on July 4th, the United States celebrates the 235th anniversary of the signing of the Declaration of Independence. (U.S. Air Force photo by Senior Airman Corey Hook)

7/6/2011 - Army Gen. David H. Petraeus, senior commander of U.S. and coalition forces in Afghanistan, greets 235 service members after they re-enlisted under his reading at Kandahar Air Field, Afghanistan, July 4, 2011. This year, on July 4th, the United States celebrates the 235th anniversary of the signing of the Declaration of Independence. (U.S. Air Force photo by Senior Airman Corey Hook)