I am proud of my service and proud of those who served alongside me. But war is about more than service and sacrifice — it’s about winning. Sixty years ago, Americans looked to Europe and Asia and saw continents liberated and despots defeated. With the Islamic State on the rampage, Americans today look to a Middle East that is humiliatingly worse off than the way we found it.

The burden of this humiliation fell hardest on Republican strongholds. Demographically, the military draws heavily from the South, rural areas and the working and middle class. And while no racial group has a monopoly on military service, white enlistees make up a disproportionate share of those wounded and killed in action. This is the very same demographic that forms the core of the contemporary Republican base. Whether they were working-class Reagan Democrats like Mamaw or committed middle-class Republicans, the people who made Mr. Bush president are the same people who sent their children to fight in his wars.

Add to this a Department of Veterans Affairs that failed to adequately care for returning troops, and it’s almost too perfect a narrative: The same leadership that failed to pacify Iraq cannot properly administer benefits to veterans. The product is combustible frustration.