By throwing its support behind Syria’s Kurds, Russia has succeeded at driving a wedge between Turkey and its NATO allies.

Kurdish fighters have recently taken advantage of Russian airstrikes in the north of Syria that have targeted Arab and Turkmen opponents of the regime of President Bashar al-Assad. Kurds now control almost the entire frontier with Turkey.

Turkey has responded by shelling Kurdish positions on the other side of the border, alarming its Western allies who see the Kurds as the most effective fighting force against the self-declared Islamic State.

Turkish fears

Turkish president Recep Tayyip Erdoğan dismissed Western criticism of the shelling of Tuesday, saying the Kurdish militias in Syria were a creation of Assad and his Russian protector.

“Right now Russia’s brutal operation, along with the Syrian regime targeting civilians, is underway,” Erdoğan said, referring to an offensive of Assad loyalists around Aleppo, the last rebel stronghold in the north.

Their aim, the Turkish leader alleged, is to create a corridor for Kurdish “terrorist organizations.”

Erdoğan’s government sees a link between the Kurdish militias in Syria and the Kurdistan Workers’ Party in Turkey, a far-left paramilitary group that fights for Kurdish independence.

Ankara fears that the emergence of a Kurdish republic in the north of Syria would exert inordinate pressure on its own Kurdish population to secede.

Partitioned

Assad has mostly left the Kurdish minority in his country alone since the civil war began five years ago.

With the help of Russian airstrikes, his regime is consolidating control of the more heavily populated western parts of Syria.

The Islamic State, a fanatical Islamist group, controls much of the eastern deserts as well as territory across the border in Iraq — where it is opposed by Kurds as well.

Priorities

The West is in the awkward position of supporting two enemies of the Islamic State who are also at war with each other: Turkey and the Kurds.

Russia, which is also on the other side of European countries and the United States in a proxy war in Ukraine, is exploiting this situation by aiding the Kurds in Syria.

It also has a score to settle with Turkey, which shot down one of its warplanes on the Syrian border last year.

There is no obvious way out of this dilemma, because the West’s allies do not share its priority of defeating the Islamic State.

Turkey’s priorities are suppressing Kurdish nationalism and hastening the fall of Assad, whom it considers — with some justification — the source of all its recent troubles. The Islamic State might even be a useful last-ditch asset against the Syrian dictator.

The Arab states supporting the rebellion similarly put bringing down Assad first, given that he is the only Arab ally of their nemesis Iran.

The Kurds, the world’s largest stateless people, naturally put defending their own land ahead of defeating the Islamists.