An 18-year-old in the United States is still barred from buying alcohol, acquiring a pilot’s license, or stepping into a casino. Yet, astonishingly, they can be enlisted in the military, trained in weapon handling, and deployed to a war zone. On the other side of the age spectrum, individuals over 39, regardless of their skills or experience, often encounter insurmountable obstacles to enlistment.Break this mold and meet Lanny Snodgrass, who, at the age of 63, became the oldest American to join the Army and complete officer basic training. It was 2003, the Iraq War had just started, and the Pentagon, grappling with a severe shortage of military doctors, momentarily relaxed age requirements. Recognizing an opportunity, Dr. Snodgrass stepped in to serve.With around four decades of experience treating veterans and active-duty military personnel, many teenagers grappling with psychiatric illnesses such as PTSD, depression, and suicidality, Dr. Snodgrass bears unique insight into the perils of sending young soldiers to war. He has seen firsthand the walking wounded, those who have served in multiple deployments and are often on the brink of despair.This book represents a culmination of these experiences. As a late-joining physician and one of the leading experts on PTSD, Dr. Snodgrass poses critical questions about the limits of service and whether these age constraints should be maintained or relaxed. He scrutinizes the age limits on military service, addressing the antiquated criteria that have remained largely unchanged for over a century. If we continue to send our young to war while overlooking the potential of older, willing Americans, tragic consequences will persist. It’s not an overstatement, then, to say that Duty Calls presents a life-and-death proposition on how to build a more resilient, professional military force.