Turkish air and ground forces are attacking northern Syria.  The target is not ISIS – the presumed threat to Turkish interests – but rather Kurdish forces that have borne the brunt of anti-ISIS ground fighting and are key to the battle for Mosul in Iraq. 

Since the July aborted coup in Ankara, the government of Recep Tayyip ErdoДџan has been making internal war against what it calls the "Gülenist threat," followers of Turkish cleric Fetullah Gülen, who ErdoДџan believes engineered the coup.  Tens of thousands of Turks have been arrested, dismissed from their jobs, and otherwise harassed.  Turkey has also been conducting an external war – either overtly or by proxy – to control sensitive areas of Iraq and Syria and short-circuit any possibility of Kurdish independence or large-scale autonomy emerging from the wreckage of wars in both those countries.

After shelling Kurdish positions just north of Aleppo, the Turkish Air Force bombed headquarters, ammunition dumps, and shelters.  Turkish sources claimed 200 dead; Kurdish sources said 10 people were killed.  They were PKK, said the Turks – members of the Peoples Workers Party, which has carried out operations inside Turkey for decades.  The People's Protection Units (YPG), however, said in a statement that the airstrikes targeted fighters from the YPG-affiliated Jaish al-Thuwar (Revolutionary Front), which was advancing against ISIS in the city of Ifrin.

Turkey makes little distinction among Kurdish groups.  The U.S. takes a different tack, agreeing that the PKK is a terrorist organization but arming and training the YPG and finding it the most effective force on the ground fighting ISIS.  A U.S. official says the particular Kurds targeted this time were not among those we have trained, so there were no Americans in the area of Turkish fire.  This time.  But the possibility of direct U.S.-Turkish confrontation is rising daily.

There has been little mention of Turkey's wars in the American press, aided by the fact that militias, rebel armies, terrorist groups, and sub-state actors sound like alphabet soup: FSA, PKK, PYD, YPG, JAN, ISIS, AQI, and more fight in Syria and Iraq.  Even when they have names, Americans are likely to find themselves confused.  How does Jaish al-Thuwar relate to the Khalid ibn al-Walid Brigade, or the Free Syrian Army or the Authenticity and Development Group, the Sun Battalion, the Al-Qousi Brigade, or the Truthful Promise Brigade?

Confusion is serving Turkey well.

There are an estimated 60 million Kurds in the Middle East and adjacent regions, divided among Turkey (25.8 million), Iran (11 million), Iraq (10.2 million), Syria (4 million), and Afghanistan (9 million).  Another 2 million are estimated to be in Europe, primarily in Germany. 

Turkey adamantly opposes independence for the Kurds, and the U.S. had trouble gaining even reluctant Turkish acceptance of Northern Iraq's regional autonomy after the 2003 ouster of Saddam from Baghdad.  The dissolution of Assad's control of Northern Syria and the possibility that Iraqi and Syrian Kurds might construct a contiguous Kurdish area appears to pose a greater problem for Turkey than the rise and spread of ISIS.  It is against the Syrian Kurds, therefore, not ISIS that Turkey has been operating for months.

In late August, Turkey directly intervened with tanks and planes to assist the Syrian Nour el-din el-Zinki rebel group in attacking Kurdish forces.  The Kurds, members of the YPG militia, had captured the ISIS-held town of Manbij, but the Turks wanted them to hand the town over to its proxy.  The U.S. caved to Turkish demands and ordered the YPG – its ally – out of town.

Following U.S. pressure on the Kurds, the Turks have increased the pace and lethality of their attacks.  Unsurprisingly, Kurdish groups have begun to challenge reliability of the West – and the U.S. in particular.  This round of fighting began just before a scheduled visit to Turkey by U.S. secretary of defense Ashton Carter.  Carter, no doubt planning to ensure continued use of Turkey's Incirlik air base to launch strikes against ISIS and to support Iraq, struck a conciliatory tone toward Ankara when asked about the airstrikes – something sure to rankle the Kurdish militias.  "With respect to Turkey, our partnership is very strong in the counter-ISIL campaign," he said.  "We're working with the Turks now very successfully to help them secure their border area."

To many in the Middle East, the United States not only appears unreliable, which is bad enough, but seems to have frequently abandoned its friends and allies, which is worse.  In the Obama administration, not only the president, but also the vice president, secretary of state, and secretary of defense bear responsibility for these impressions.  While Turkey is, by treaty, an American ally and a NATO member, the U.S. has to either rein in the Turks or face the consequence of a powerful and reckless Turkish government shooting up Turkey and its neighborhood – and our allies.

If the Kurds are really the West's best hope for a ground force against ISIS, there are several steps the U.S. can and should take to impress upon the Turkish government the seriousness with which we take their aggression in Syria and Iraq.

As matters of policy, the U.S. should:

• Insist that Turkey stop attacks on Kurds outside Turkish territory.
• Demand that Turkey remove its forces from Iraq and Syria.
• Demand that ErdoДџan restore rule of law to Turkey and end the persecution of Gülenists and Kurds.

Moving from demands to action, the U.S. should:

• Stop delivery of military hardware to Turkey, including spare parts, and demand that all NATO allies do the same.
• Stop cooperation and any coordination with Turkey's military and intelligence organs until Turkey complies.
• Increase the arms flow as well as intelligence and other cooperation with the Kurds to ensure they are defended as well as possible.

Without these steps, Turkey, a powerful country, will become a genuine threat to the region as it tries to reestablish a modern form of Ottoman suzerainty.