Before entering ground combat, we have to fix the political problem. It would be insane to repeat our previous mistake and train an army to fight for the current Shiite government. Last year we trained not a single Sunni soldier, and our dollars continue to flow through Baghdad to Shiite militias.

Worse, the most famous general in Iraq today is Qassim Suleimani, the commander of the Iranian paramilitary Quds Force, which has expanded its reach deep into Iraq. It is infuriating that the road to Iranian influence in Baghdad is drenched with American blood.

Even with a thousand American advisers, Shiite soldiers today won’t fight for desolate Sunni lands. If we’re committed to a yearslong effort, money should flow directly to the end recipient of our choosing — whether that be the Iraqi Army, Kurds or Sunni tribesmen. Our current half-strategy opposes one enemy — the Islamic State — but benefits a much bigger threat, Iran.

If we don’t get the politics aligned with a commitment to destroy the Islamic State, our advisers should expect the same heartbreak as those of us who fought in Operation Iraqi Freedom, and our fathers before us in Vietnam.