To understand why President Trump’s withdrawal from Syria has unleashed such violence, it helps to see this moment as the culmination of a problem that has been building since the conflict began.
In the war’s first days, northern Syria’s large Kurdish population effectively seceded and, later, came to control the area.
The war’s many actors, Kurds included, knew this was, in the long term, not sustainable.
The Kurds were too weak to hold out forever. But they were too strong, too fearful of outside dominance and, over the course of the war, had built too many institutions of self-rule to be simply folded back into the Syrian state.
At the same time, the outside world saw Kurdish autonomy as essential to running out the Islamic State, but knew it was, long-term, a barrier to ending the war. Syria’s government would never accept losing the north’s oil and agricultural wealth. Turkey’s government, just across the border, saw permanent Kurdish autonomy as an unacceptable threat.
This became the northern Syria problem: How to reconcile these contradictions and create a sustainable, broadly acceptable equilibrium in northern Syria. Only then could the world hope to make the Islamic State’s defeat permanent and to end an eight-year war that has killed hundreds of thousands and displaced millions.
But the northern Syrian problem never got resolved.
Instead, the United States kept what was known to be an unsustainable status quo “frozen in place,” said Frances Z. Brown, who served as a director on the National Security Council under President Barack Obama and Mr. Trump.
That status quo served useful ends for Washington, first to drive out the Islamic State and later, under Mr. Trump, as a potential bargaining chip with the Syrian government and its allies.
American officials knew that the northern Syria problem would have be resolved, Ms. Brown said, and that only Washington had the leverage and relationships to do it. But other priorities took precedence.
The contradictions widened. Northern Syria became a tinderbox. An American troop presence kept it from exploding — until last week, when Mr. Trump suddenly recalled those troops and, in what amounted to tossing a match, invited Turkey to invade.
Now, years of unresolved tensions are exploding as Turkish troops, Syrian government troops and their Russian allies, and Kurdish forces all rush to impose a new equilibrium.
The northern Syria problem has gone from a mostly political issue to an armed struggle, opening a violent new chapter in a war that only a week ago had seemed to be winding down.
The Origins of a Problem
Countries often fracture during a civil war. Rebels seize territory. Minorities declare independence. The pieces seem like they will never fit back together until, after years or decades of peacekeeping missions and power-sharing deals, they do.
Syria’s disintegration was unusual in degree, partly because of the government’s brutality and the crisscrossing interventions that helped pull the country apart, but not in kind.
Still, northern Syria fractured in ways that made it particularly complicated to reassemble.
As war broke out, long-oppressed Kurds rose up as much out of self-defense as to carve out a degree of autonomy.
Syria’s government, focused on other fights, largely let them be.
The two sides, nominally opposed, needed each other. Syrian leaders in Damascus, the capital, would rather that Kurds held territory that might otherwise be taken by rebels that sought the government’s downfall. And the Kurds, not quite organized enough to fully control the north, needed Damascus to continue funding local government salaries and institutions.
That cold peace became far less stable with the involvement of the United States and Turkey.
For Turkey, every inch of Kurdish expansion across Syria and every day that the Kurds deepened their autonomy posed an ever-growing threat.
But as Turkey opposed the new order in northern Syria, the United States moved to deepen it. Adopting Syria’s Kurds as its ground force against the Islamic State, Washington gave them the financial, diplomatic and military cover to retake extremist-held territory.
Complicating matters further, the United States and Turkey are NATO allies with a litany of shared issues. This forced each country to accommodate the other’s concerns even as their positions in northern Syria came into greater conflict.
Northern Syria became split along two political axes: first Kurdish-Syrian, and now American-Turkish.
The first of those was tenuous on its own, said Ms. Brown, who is now an analyst at the Carnegie Endowment for International Peace. But it was the second that created “an unsustainable equilibrium.”
Northern Syria became ground zero for contradictions in Mr. Obama’s approach to Syria and, more recently, Mr. Trump’s, said Aaron Stein, director of the Foreign Policy Research Institute.
Mr. Obama had demanded that Syria’s leader, Bashar al-Assad, step down. But, in practice, he took steps to weaken but not remove Mr. Assad. And after the rise of the Islamic State, Mr. Obama prioritized defeating the extremist group.
Backing Syria’s Kurds, Mr. Obama became the patron of breakaway Syrian territory — and the owner of the northern Syria problem.
But the contradiction in his policy prevented Washington from resolving it.
The Kurds and Damascus could not reconcile without Washington’s acquiescence, which Mr. Obama’s stated opposition to Mr. Assad prevented him from granting. At the same time, Mr. Obama’s emphasis on defeating the Islamic State required him to allow the Kurds and Damascus to maintain their cold peace.
This opened another contradiction: The United States pledged to accommodate both the political aspirations of the Syrian Kurds and Turkey’s vehement opposition to Kurdish autonomy.
So the United States froze the cold peace in place, with plans to resolve the crosscutting disagreements after the Islamic State had been fully defeated and the north stabilized.
Mr. Trump came into office dropping demands for regime change in Syria, seemingly “resolving the tension in American policy,” Mr. Stein said.
“It was in the execution that we got back into tension with ourselves,” he said.
As with other foreign policy initiatives, Mr. Trump and members of his senior staff seemed to pursue diverging agendas.
While the president promised withdrawal, Pentagon and State Department officials reassured Kurdish groups with promises to stay. Last year, the State Department, bowing to Turkish objections, quietly blocked a Kurdish effort to begin reconciliation talks with Damascus.
James F. Jeffrey, the Trump administration’s special envoy for Syria, has described America’s presence as a bargaining chip to secure not just the Islamic State’s defeat but also political change in Syria and a rollback of Iranian influence.
“It was, ‘We’re going to use a permanent occupation in the northeast to force Bashar al-Assad to cut his own head off,’” Mr. Stein said, describing American demands for Mr. Assad to hold elections that would likely see him lose power.
These “maximalist goals,” Mr. Stein said, created the conditions for open-ended occupation, locking the status quo in place.
And they opened a new set of contradictions: The United States was now promising the Kurds a secure future while signaling it might trade the Kurdish territory away for broader goals.
But Mr. Trump’s opposition to an open-ended commitment in Syria and his habit of lashing out when he feels boxed in by his staff made the status quo unlikely to hold.
Beyond that, the approach would work only as long as Turkey tolerated an American-Kurdish ministate on its border — something Turkey insisted it could not allow.
“It was always built on a house of cards,” Mr. Stein said. “Everything was in tension.”
Sure enough, Mr. Trump announced an American departure from Syria late last year, prompting staff resignations that led Mr. Trump to reverse his plan. But the northern Syria problem remained unresolved, waiting to burst.
“Ten months later, the United States is still the only pole holding up the tent in northern Syria,” Aron Lund, an analyst at the Century Foundation, wrote in a policy brief last week. “And Trump seems to be saying that time is up.”
A Deepening Problem
Mr. Trump’s sudden departure has collapsed northern Syria’s already fragile equilibrium. The result is a political and security vacuum that the major forces — Turkish, Syrian government and Syrian Kurd — are scrambling to fill.
In a cycle familiar to such conflicts, all sides feel compelled to shape the new order to their advantage before others can do so first.
That creates an incentive for violence and, because political power in Syria derives from demographics, for atrocities of the sort that have punctuated the war’s worst moments.
The northern Syria problem, far from resolved by the American departure, is entering a new chapter that could be far bloodier, more chaotic and more destabilizing.