On Tuesday morning, Turkey did something strange. As the Islamic State in Iraq and Syria (ISIS) advanced through the Syrian town of Kobane right along Turkey's border, the Turkish military sent F-16s to bomb Kurdish territory in eastern Turkey — just next to Iraq. Allegedly, it was targeting the Kurdish Workers' Party (PKK), a militant group that Turkey had been negotiating with for a little over a year. Turkey claims the PKK broke a ceasefire between the two sides first. But, at this point, "who started it?" isn't really the big question. "Where does this go next?" is.
This could be bad, and not just for Turkey. The PKK is playing a huge role in the Kurdish fight against ISIS, just across the Turkish border. If the Turkey-PKK conflict restarts in earnest, the Syrian civil war will get even more intractable. And ISIS would almost certainly emerge as a big winner.
What is the PKK and why is Turkey bombing it?
It is very hard to overstate how big a deal the PKK is for Turkey. The PKK waged a violent, terrorist campaign for decades; Turkey sees them as one of its greatest national security threats.
As you can see in the map above, Turkey has a significant Kurdish minority concentrated in the country's east. In the 1970s, a number of these Kurds began organizing to demand autonomy and special protections for Kurdish rights to guarantee equality. The government, uninterested in compromise, repressed the Kurdish opposition. That gave rise to a more violent Kurdish resistance movement — specifically, the PKK, founded in 1978.
Abdullah Öcalan, the PKK's (currently jailed) leader, officially launched the Kurdish insurgency in August 1984. The PKK was both a Kurdish nationalist and a Marxist group: they wanted an independent, socialist Kurdistan (they've since ratcheted their demands down to autonomy inside Turkey). The war, marked by PKK terrorist attacks and an unbelievably brutal Turkish response, has killed about 40,000 since the on-again, off-again fighting began in 1984. The violence peaked in the early 90s, though there was a bloody resurgence in 2012 — arguably linked to the Syrian civil war.
In 2013, Turkey and the PKK negotiated a ceasefire as part of discussions over a permanent peace treaty. The peace process, as it's called, hasn't gone very far — and right now, it's on the brink of collapse.
The current conflict is about ISIS' advance on Kobane — a city in Syria
Turkey and the PKK are on the brink of war because of ISIS. Here's why: ISIS is threatening to slaughter the largely Kurdish residents of Kobane, a Syrian town on the border with Turkey, and Turkey is refusing to intervene to stop it. But the reason that Turkey is refusing to intervene is more complicated.
Early in the Syrian civil war, Syrian leader Bashar al-Assad's government essentially ceded Kurdish-majority chunks of northern Syria to Kurdish militias. Strategically, it was a canny move: all the Kurds really wanted was autonomy, and Assad had just given it to them. Therefore, they had zero interest in joining the rebellion against the Assad government.
Since then, the Kurds have had a de facto truce with Assad — but they've fought numerous times with non-Kurdish Syrian rebels, particularly the Islamists.
This also plays into Turkish politics. The Kurdish group that controls this territory in Syria, the Democratic Union Party (PYD), is a PKK offshoot. The PKK has a lot of fighters operating in PYD areas. And Turkey is very, very unhappy about Syria becoming safe haven for the PKK.
Turkey is so upset, in fact, that it is refusing to intervene to stop an ISIS advance on the Kurdish town of Kobane. After months of fighting, ISIS is threatening to overtake the city completely. American airstrikes have helped the PYD fighters in Kobane hold off ISIS, but the PYD is begging for Turkish help in beating back the ISIS advance. Turkey's military, after all, is just across the border. But Turkish officials are implying, if somewhat vaguely, that they'll only intervene if the PYD severs its links to the PKK and joins the rebel-led fight against Assad.
Meanwhile, the Kurds within Turkey are furious about the Turkish government's inaction. There've been mass protests in Turkish Kurdistan, which have gotten bloody — over 30 people have been killed, mostly in clashes between pro- and anti-PKK protestors. Kurdish leaders with the PKK and PYD say they'll hold Ankara accountable if ISIS takes Kobane.
A few days after the fighting broke out in eastern Turkey, PKK leaders told the New York Times that the peace process would be over if Turkey refused to save Kobane from ISIS. "Negotiations cannot go on in an environment where they want to create a massacre in Kobani, Cemil Bayik, a top PKK leader, said. "We will mobilize the guerrillas."
In other words, the PKK threatened to attack Turkey if it didn't intervene to save Kobane's Kurds. Needless to say, the Turkish government has not responded well to these threats, attacking the PKK instead. The current round of Turkey-PKK fighting may very well be the beginning of a new war.
A new PKK-Turkey war would be a disaster — for Turkey, Syria, and the region
Suppose these clashes between Turkey and the PKK devolve back into war. What happens?
For one thing, heavily-Kurdish eastern Turkey would become a war zone again. Potentially, so would northern Syria, which is also mostly Kurdish. Turkish war planners might not be able to ignore the huge PKK safe zone just across the border from them, and could respond with air strikes or potentially even ground troops. If Turkey starts attacking Kurdish militias in Syria, that would indirectly help ISIS, which is currently fighting those same Kurds.
The fighting could even spread to Iraq, where there is also a large Kurdish community, but one that the US is currently committed to protecting with airstrikes. A recent Turkish airstrike hit a town just 8 miles from the Iraqi border; the PKK is assisting Iraqi Kurdish forces in their own front against ISIS. In 2011, Turkey bombed PKK encampments in Iraq, and there's little stopping them from doing it again.
In humanitarian terms, this would be a disaster. A wider war like this would be bound to get a lot more people killed, especially the Kurds who would be squeezed between ISIS and Turkey.
Moreover, it'd be a catastrophe for the American-led coalition against Assad. The US wants Turkey to help the Syrian Kurds in their fight against ISIS in northern Syria. If the Syrian Kurds and Turkey fought each other instead, that is two fewer militaries combatting ISIS.
Turkey also wants to depose Assad, and is training and equipping Syrian rebels to do that. A war between Turkey and Syrian Kurds could suck in Syrian rebels who are backed by Turkey, further complicating the war and distracting from the fights against ISIS and Assad.
This is the nightmare scenario. It's not certain, fortunately, that the PKK-Turkey conflict will reignite, or even if it does that it will spiral into a wider conflict. But if this really does come to pass, then the Middle East's worst conflict could get much worse — and ISIS would become that much harder to defeat.