As Christmas 2011 approached, U.S. Army medic Shawn Aiken was once again locked in desperate battle with a formidable foe. Not insurgents in Iraq, or Taliban fighters in Afghanistan - enemies he had already encountered with distinguished bravery.
This time, he was up against the U.S. Defense Department.
Aiken, then 30 years old, was in his second month of physical and psychological reconstruction at Fort Bliss in El Paso, Texas, after two tours of combat duty had left him shattered. His war-related afflictions included traumatic brain injury, severe post-traumatic stress disorder (PTSD), abnormal eye movements due to nerve damage, chronic pain, and a hip injury.