Almost daily, Greek and Turkish aircraft and ships fight mock battles over disputed oil and gas rights in the eastern Mediterranean.
Since the loss of much of the Christian Balkans to the Ottomans in the 15th century, Greece and what would later become modern Turkey have been rivals, outright enemies and often at war.
Mutual NATO membership and shared Cold War fears of Soviet Russia did not stop the two from almost going to war after the Turkish invasion of Cyprus in 1974.
Still, the current escalation seems weird. Most territorial claims and disputes over borders were settled almost a century ago, and the two countries have had mass population exchanges.
Why, then, does the divide still run so deep?
Turkey is a Muslim country and was once the Ottoman Empire that ruled much of the Islamic