A killer earthquake in Turkey's mainly Kurdish southeast a fortnight ago sparked a genuine show of popular support and charity, but the ugly rhetoric of nationalism was not far behind. And the vitriol comes from the mainstream, not just the political fringes.

The 7.2-magnitude quake in Van province on 23 Oct killed about 600 people and injured thousands more. It hit during a period of renewed violence between the Turkish army and the Kurdistan Workers Party (PKK), an outlawed guerrilla group that has waged an armed campaign for Kurdish autonomy since 1984. Just four days before the quake, the PKK killed 24 soldiers in an ambush in neighbouring Hakkari province, sparking convulsions of national grief.

With feelings still raw after the attack, some public figures expressed outright racist sentiment towards victims of the earthquake in the hours after it rocked Van. Breakfast show host Muge Anli spat on national television: "When we feel like it, we throw stones at police and kill soldiers as if we were bird hunting in the mountains. Then, when something happens, we say, 'Police, soldiers, come.' We need a balance...People need to know their place." And Duygu Canbas, a news anchor, departed from the teleprompter to express racist-tinged sympathy over the tragedy. "Even if it is in Van, all of Turkey is sad about this news," she said during a live broadcast.

Anli and Canbas were speaking for those Turks who equate Kurds with the PKK. For these people, Kurds had it coming to them. Though both women were widely criticised and soon offered apologies, the comments are still a crack in the veneer of national unity, the mandate of successive governments since the birth of modern Turkey. Last Saturday marked the 88th anniversary of the founding of the Turkish Republic. Official celebrations were cancelled out of respect for the loss of life in the earthquake, causing outrage on social networking sites. Not everyone obliged with the show of respect: About 1,000 motorcyclists held an impromptu ceremonial ride-out in central Istanbul, their bikes festooned with Turkish flags. (In this topsy-turvy country, even bikers are fervent nationalists, while elsewhere they are outlaws, at least on the weekends.)

Turks' inability to distinguish between Kurds - who make up some 20% of the population - and the PKK mirrors the trouble Americans have distinguishing Muslims from terrorists, the British had when separating Catholics from the IRA and the Spanish in seeing ETA everywhere there are Basques. It is a mistake the Turks have made before when ridding themselves of established ethnic populations before and after 1923. Even today many still refuse to accept that there is an independent Kurdistan in northern Iraq, even though it is codified in the Iraqi constitution. For decades, Kurds were not even recognised as a distinct ethnic group and were instead referred to as 'Mountain Turks'. The Kurdish language was banned outright until 1991.

Nationalist dogma papers over many cracks, including the institutional corruption that leads to almost no prosecution for the criminal disregard of construction standards that leads to avoidable deaths in a country crisscrossed by fault lines. The sending of tax money specifically set aside for earthquake-proofing is spent on other government projects. Prime Minister Tayyip Erdogan calls on families to have three children in a country with one of the youngest populations in Europe and highest rates of childhood poverty to stave off a pension crisis that will inevitably arise.

In Turkey, nationalism lets political parties of all stripes hide behind personalities instead of policies and obedience to a national cause rather than public-service-led government. It stifles debate, scuppers reconciliation with the past and engenders cultural homogeneity. It can, quite literally, bring down the walls on an otherwise great nation.

Out of tragedy, community is often born. Turkey realised that in 1999 when successive earthquakes here and in Greece prompted mutual outpourings of aid and led to reconciliation between the arch enemies. The earthquake in Van offers Turkey another chance at such "earthquake diplomacy," this time inviting it to make peace with its own citizens.

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