Everyone from the Russian foreign minister, Sergei Lavrov, to the EU’s Catherine Ashton is “urging restraint” as Turkey retaliates for Syrian shelling over the border yesterday. But despite Turkish anger about the killing of five of their citizens, in the long-term they may be more concerned about what they see as Syrian “meddling” in Turkey’s internal conflict with the Kurds.

Over the summer, attacks by the Kurdish Workers’ Party, the PKK, suddenly increased after a decade of relative quiet.

While the world concentrated on what was happening inside Syria, the PKK attacked Turkish military patrols and took control of several dozen villages on the Turkish side of the border. Turkish commentators see the hands of Syria and Iran.

“We are at war with Syria and its regional allies,” wrote Suat Kiniklioglu, a foreign affairs advisor to the governing AK Party back in August. “The sharp increase in Kurdistan Workers’ Party (PKK) terror incidents is nothing but an effort by the Assad regime to take the war beyond Syria’s borders.”

Everyone, of course, is meddling across borders. The Turks are funding and arming the Free Syrian Army, the main guerrilla group seeking the overthrow Bashar al-Assad’s government and allowing its fighters to retreat across into Turkey to rearm and regroup. Support for the PKK is the Syrian government response.

The Kurds, who have no nation of their own and are spread across Turkey, Iran, Iraq and Syria, have long resented Turkish government rule, which has frequently been repressive. Their cause has been exploited by all regional governments to score points against each other since the borderlines were drawn at the end of the Ottoman Empire. Successive Turkish governments have used the military to put down Kurdish unrest, which has contained the PKK but done nothing to appease ordinary Kurds.

Now, government and opposition in Syria are vying for Kurdish support – they’re seen as “swing voters”, whose allegiance could tip the conflict one way or the other.

Hopefully, the current skirmishes on the Syrian-Turkish border will cease and diplomacy will take over. But expect more border trouble as Syria tries to use Kurdish hostility to the Turkish government to boost its position in the border areas.

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