Defeat for the U.S. allies in northern Iraq is a victory for Iran.

A central tenet of the Trump foreign policy, a work in progress, has been that the U.S. would rebuild its relationship with America’s allies. That commitment is being put to the test in northern Iraq. On Monday Iraq’s army, assisted by Iranian forces, launched a major assault on the Kurds in the northern Iraqi city of Kirkuk. Across the length of America’s recent history with Iraq, we have had no more reliable ally than Iraq’s Kurds and their fighting force, the Peshmerga. So far the Trump Administration has said little about the attack on the Kurds. “We’re not taking sides, but we don’t like the fact that they’re clashing,” President Trump told reporters at the White House Monday. “We’ve had, for many years, a very good relationship with the Kurds, as you know. And we’ve also been on the side of Iraq, even though we should have never been in there in the first place. But we’re not taking sides in that battle.” But if the U.S. allows one of its most visible allies to be defeated in the Middle East, make no mistake: Other allies in the region will notice and start to recalculate their relationship with the Trump Administration.

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