Lionel Beehner

Opinion columnist

“We must always have the backs of our allies, if we expect them to have our back,” Nikki Haley, President Donald Trump's former ambassador to the United Nations, wrote on Twitter.

That is the storyline being told after Trump's abrupt announcement, following his phone call with his Turkish counterpart, for U.S. forces in Syria to pull back from their positions and allow Turkey to create its long-planned "safe zone."

A similar theme emerged when the United States sought to withdraw forces from other parts of the globe, as naysayers invoked the abandonment of Iraq's Shiites in 1991 or our withdrawal of support for Afghan resistance fighters after the Soviets left in 1989. In both cases, the result was an eventual costly American invasion.

ISIS fears overstated

The fear in Syria is that our pullout will result in a security vacuum filled by an Islamic State caliphate, from which attacks against Americans could arise.

ISIS is not defeated, as Trump took to Twitter to exclaim this past weekend. Yet nor is the threat as grave as his naysayers suggest. Given the number of outside powers with a vested interest in Syria — Iran, Russia, Israel, Turkey — it is unlikely that ISIS will reconstitute its caliphate. Nor is it likely that America's 1,000 troops there would make much of a difference.

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The bigger fear is twofold. First, the symbolism of the withdrawal and wink-wink-nod-nod Trump gave to Turkey could portend the future decline of American influence in the region. We are bystanders, whether it involves alleged Iranian-led attacks against Saudi oil deposits or a Turkish invasion across its southern border, Washington is largely unable to intervene, much less shape events. Nobody wants a wider war, not least an American public distracted by a pending impeachment.

Second, as I have noted on these pages in the past, is that "safe zones" rarely stay safe, and that Washington's tacit approval of a Turkish offensive into Syria sends a dangerous message to other countries twitchy about invading their neighbors.

Countries like Turkey have largely used restraint when it came to using military force across borders. Turkey has carried out dozens of cross-border operations into northern Iraq, but generally never strayed further than a few miles from the border nor left its troops there as occupying forces. Ditto India into Pakistan-administered Kashmir.

Incoherent Syria strategy

But Trump, with his latest impulsive gesture, has green-lighted such operations. Turkey's planned military offensive to "clear" the area of Kurdish fighters, who are nominally aligned with the United States and act as unofficial "proxies" of ours, could result in a bloodbath. Turkey's fear is that Kurds both within and beyond its borders will agitate for independence, by arms if necessary. For some Turks, the Kurdish issue is an existential one. A "safe zone" has always been a fig leaf by Ankara to use military pressure to keep down Syria's Kurds and exert greater influence in its northern areas where control is more fluid.

Turkey also houses 3.6 million Syrian refugees already and has used them as bargaining chips, threatening to send them northward into Europe.

The United States has effectively used Syria's Kurds, who are good fighters, as its infantry in northern Syria, given the lack of any public interest to see American boots on the ground there in significant numbers.

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But let's not overstate our shared common values or interests. The so-called Syrian Democratic Forces, of which the Kurdish People's Protection Units, or YPG, constitute a significant part, also includes an estimated 2,000 Islamist fighters related to ISIS. In fact, Idlib province in Syria's northwest, where Turkey's "safe zone" would be installed, is estimated to host more foreign fighters than any place since 1990s-era Afghanistan. Hardly a recipe for a "humanitarian corridor" or a "de-escalation zone."

Nor should anyone overstate American influence in Syria. Our military footprint has always been small compared with that of Turkey's, Iran's or Russia's. Even though symbolically the withdrawal may hurt morale among Syria's dwindling opposition, it does not necessarily mean the reconstitution of the caliphate.

Unlike Nikki Haley's comment above, the real fear is not that nobody will partner with us going forward. It's Washington's lack of a coherent strategy in Syria, going back to President Barack Obama. Syria is what happens when wars are left to fester and the fighting is outsourced to dubious groups.

Lionel Beehner, a member of USA TODAY's Board of Contributors, is an assistant professor and director of research at West Point's Modern War Institute.