https://geopoliticalfutures.com/the-origins-of-new-us-turkish-relations/
For several years, there has been a significant shift underway in U.S. strategy toward the Middle East, where Washington has consistently sought to avoid combat. The United States is now compelled to seek accommodation with Turkey, a regional power in its own right, based on terms that are geopolitically necessary for both. Their relationship has been turbulent, and while it may continue to be so for a while, it will decline. Their accommodation has nothing to do with mutual affection but rather with mutual necessity. The Turkish incursion into Syria and the U.S. response are part of this adjustment, one that has global origins and regional consequences.
Similarly, the U.S. decision to step aside as Turkey undertook an incursion in northeastern Syria has a geopolitical and strategic origin. The strategic origin is a clash between elements of the Defense Department and the president. The defense community has been shaped by a war that has been underway since 2001. During what is called the Long War, the U.S. has created an alliance structure of various national and subnational groups. Yet the region is still on uneven footing. The Iranians have extended a sphere of influence westward. Iraq is in chaos. The Yemeni civil war still rages, and the original Syrian war has ended, in a very Middle Eastern fashion, indecisively.
A generation of military and defense thinkers have matured fighting wars in the Middle East. The Long War has been their career. Several generations spent their careers expecting Soviet tanks to surge into the Fulda Gap. Cold Warriors believed a world without the Cold War was unthinkable. The same can be said for those shaped by Middle Eastern wars. For the Cold War generation, the NATO alliance was the foundation of their thinking. So too for the Sandbox generation, those whose careers were spent rotating into Iraq or Afghanistan or some other place, the alliances formed and the enemies fought seemed eternal. The idea that the world had moved on, and that Fulda and NATO were less important, was emotionally inconceivable. Any shift in focus and alliance structure was seen as a betrayal.