For every US soldier or Marine deployed in harm's way overseas, three remain in the US working to support the mission. But, as the BBC's Katie Connolly finds, missing the defining deployments of a military era can be difficult to come to terms with. When Jay Agg signed up for the US Marine Corps after the 9/11 attacks, he knew he risked being severely injured, perhaps losing limbs. He knew he might even lose his life. Yet, much to the surprise of many civilians, when his service came to an end in 2006 and he hadn't served in a combat zone, Mr Agg was sorely disappointed. Some might imagine that soldiers who don't get deployed breathe an enormous sigh of relief, pleased that they are remaining on safe soil, far from danger. Check this out ...