But what’s the excuse for those who should know better? I’m talking about those who suddenly think the U.S. owes greater loyalty to a battlefield ally (the Kurds) than we do to a longstanding member of NATO (Turkey). I’m also talking about those who should know very well that the Kurds of Syria are dominated by the Kurdistan Workers Party (PKK), a far-left organization known for practicing terrorism and eager to foment civil unrest as a means to helping the Kurds of Turkey to establish an independent state. One needn’t be an Erdogan apologist to recognize that this constitutes a threat to the territorial integrity of a treaty ally. Then-Secretary of State Hillary Clinton certainly understood it when she vowed during a visit to Turkey in August 2012 that “Syria must not become a haven for PKK terrorists whether now or after the departure of the [Bashar] al-Assad regime.”

If the U.S. military was able to form an alliance of convenience with the Syrian Kurds in order to achieve a mutually advantageous goal (defeating and dispersing the caliphate of the Islamic State), great. But that doesn’t mean that we should be risking our far more geopolitically important relationship with Turkey because we’re now best buddies with and long-term protectors of a group we treated with well-founded suspicion less than a decade ago.

Then there’s the matter of what exactly we’re even doing in Syria. Yes, our actions in Iraq helped to set events in motion that ultimately precipitated the Syrian civil war, and its consequences have been horrific. But that doesn’t mean there is anything the U.S. could have done or could do now to produce a better outcome. Obama understood this, which is why he resisted getting involved — at least until the rise of the Islamic State required it.