Kristin Underwood, Sacramento, CAhttp://www.treehugger.com/files/2009/05/who-uses-the-most-energy-in-the-us-the-military.php Image via: Getty Images. In 2007, US Department of Defense (DOD) spent $13 billion USD on fuel and this number jumped to $20 billion USD in 2008. With the military planning on moving forces from Iraq to Afghanistan this...