Daniel Bolger is a retired U.S. general who has written a book about why he thinks the U.S. lost these two wars.

Why exactly did American military leaders get so much so wrong? Bolger floats several answers to that question but settles on this one: With American forces designed for short, decisive campaigns, the challenges posed by protracted irregular warfare caught senior officers completely by surprise.

Since there aren’t enough soldiers — having “outsourced defense to the willing,” the American people stay on the sidelines — the generals asked for more time and more money. This meant sending the same troops back again and again, perhaps a bit better equipped than the last time. With stubbornness supplanting purpose, the military persisted, “in the vain hope that something might somehow improve.”

Toward what end? Bolger reduces the problem to knowing whom to kill. “Defining the enemy defined the war,” he writes. But who is the enemy? Again and again, he poses that question, eventually concluding, whether in frustration or despair, that the enemy is “everyone.”

Well, if you can’t figure out who you are fighting or why, it is not likely that you will ever be able to say you accomplished your objective. These were really wars fought for no obvious reason, and blowback may only be starting. Hopefully lessons were learned.