U.S. President Joe Biden has fulfilled a long-pending American promise by recognising the mass killings of Armenians by the Ottoman Turks in 1915-16 as “an act of genocide”, but the move has clearly infuriated Turkey, a NATO ally. In 2019, both Houses of the U.S. Congress passed resolutions calling the slaughter by its true name, but former President Donald Trump, like his predecessors, stopped short of a formal recognition of the genocide, mainly because of Turkish opposition. Ankara has challenged the “scholarly and legal” basis of Mr. Biden’s announcement and warned that it will “open a deep wound”. Up to 1.5 million Armenians were estimated to have been killed during the course of the First World War by the Ottoman Turks. When the Ottoman Empire suffered a humiliating defeat in the Caucasus in 1915 at the hands of the Russians, the Turks blamed the Armenians living on the fringes of the crumbling empire for the setback. Accusing them of treachery, the Ottoman government unleashed militias on Armenian villages. Armenian soldiers, public intellectuals and writers were executed and hundreds of thousands of Armenians, including children, were forcibly moved from their houses in eastern Anatolia (modern-day Turkey) to the Syrian desert. Many died during this exodus and many others, after reaching the concentration camps in the deserts. Turkey has acknowledged that atrocities were committed against Armenians, but is opposed to calling it a genocide, which it considers as an attempt to insult the Turks.

Mr. Biden’s move comes at a time when the relationship between the U.S. and Turkey has been in steady decline. In 2016, Ankara accused the U.S.-based Turkish Islamic preacher Fethullah Gülen of being the mastermind of a failed coup, and asked the U.S. government to extradite him, a demand Washington paid no attention to. Turkey’s decision to buy the S-400 missile defence system from Russia, despite strong opposition from the U.S., prompted American leaders to oust Turkey from the F-35 fighter jet training programme and impose sanctions on their ally. When Mr. Biden assumed office, Turkish President Reccep Tayyip Erdogan had sent feelers for a reset, saying Turkey needed help from the West to resolve the Syrian crisis. But Mr. Biden’s move on the Armenian killings appears to have widened the cracks. For Turkey, this overreaction to anyone calling the Armenian massacre a genocide is not doing any good in foreign policy. Instead of being defensive about the crimes of the Ottoman empire, the modern Turkish republic should demonstrate the moral courage to disown the atrocities. It shouldn’t allow the past to ruin its present interests.