To describe Turkish President Recep Tayyip Erdogan as “mercurial” is akin to describing the weather in Antarctica as “chilly.” At the moment, Erdogan is in the midst of an extremely violent purge of every segment of civil society: judges, journalists, educators, army officers and any and all real or imagined critics of his regime in the aftermath of a  failed coup attempt last week. 

Instability and authoritarianism in Turkey have major international implications.

Since 1952, Turkey has been a full member of the North Atlantic Treaty Organization, and its historically strong army is a key component in NATO’s bulwark against hostile actions from Russia. Turkey also has sought membership in the European Union, which could be derailed if Erdogan reinstates the death penalty as part of his bloody crackdown. 

Turkey historically had cordial relations with the State of Israel and, after a period of estrangement, those ties were put on a path towards reconciliation last month.

Erdogan burst upon the international scene when his Islamic Justice and Development Party (AKP) won parliamentary elections in 2002. The following year, he began an 11-year tenure as prime minister. The AKP was initially described as a “moderate Islamist” party that attempted to find a middle path between the militant secularism of Mustafa Kemal Ataturk, modern Turkey’s founder, and a theocratic Islamist state along the lines of Iran under the ayatollahs.

Following the example of Russian President Vladimir Putin, Erdogan gradually shifted more executive power from the office of prime minister to that of the president. He pushed through a constitutional change to consolidate most executive power in the president and assumed that post on Aug. 28, 2014.

When Erdogan first assumed executive powers, there were hopes that he would evolve into a truly moderate, if mildly Islamist, Turkish leader. But his behavior in office — shifting positions on combatting ISIS, relations with Israel and his NATO partners — has been erratic, provoking concern about how dependable Turkey is as a major ally.

Erdogan initially moved toward some kind of peaceful resolution with Turkey’s large Kurdish population. But in typical Erdogan fashion, he abruptly turned against the Kurds and resumed his efforts to crush the Kurds with military force.

Similarly, Erdogan reversed a decades-long cordial relationship between Turkey and Israel by organizing and funding the so-called Gaza Freedom Flotilla, an effort to run the Israeli blockade of the Gaza Strip. On May 31, 2010, Israeli forces boarded six of the flotilla’s ships from speedboats and helicopters. Israeli troops landed on the deck of the Mavi Marmara and were greeted with violent resistance from several activists aboard. Several Israeli troops were injured, and nine Turkish citizens were killed.

The Israeli raid was greeted with widespread international condemnation, and Erdogan called for Israel to be punished for its “bloody massacre” and “state terrorism.” Relations between Turkey and Israel remained strained until June 27, when the two countries announced a reconciliation agreement. 

Israeli Prime Minister Benjamin Netanyahu has said that the coup attempt and subsequent crackdown will not affect the restoration of  ties, but only time will tell whether Erdogan will stick to the new understandings.

After the recent savage attack at the Istanbul Airport by ISIS terrorists, Erdogan indicated his desire to fully join the fight against ISIS. Up until that horrific act of ISIS terrorism, Turkey had focused its attacks in Syria on Kurdish factions that were fighting alongside the United States and its allies to defeat ISIS. Turkey has also left its border with Iraq wide open to hundreds of young ISIS recruits from the West, allowing them to freely enter and leave Turkish territory. Only recently has Turkey closed its border to such reckless actions.

Since the onset of the Syrian civil war in 2011, Turkey has become a haven for refugees. More than 1.9 million had arrived as of August 2015. Since the ISIS attacks, Turkey has agreed to allow U.S. warplanes to use Turkish military bases to attack ISIS targets in Syria and formally joined the U.S.-led air campaign against ISIS.

Erdogan had in previous years been allied with an Islamist Turkish leader named Fethullah Gülen, who has been living in self-imposed exile in Pennsylvania since the late 1990s. Erdogan, who had a falling out with Gülen, has blamed him for instigating the coup and has demanded that the United States extradite him to Turkey to face formal charges. Secretary of State John Kerry said the matter would need to be investigated before any extradition could be considered.

Winston Churchill, in a radio address on Oct. 1, 1939, famously said, “I cannot forecast to you the action of Russia. It is a riddle wrapped in a mystery inside an enigma.” 

Actually, Russia’s actions then and now have not been all that difficult to forecast. Russia will act only in accordance with its perceived self-interest. Turkey under Erdogan is indeed a riddle wrapped in a mystery inside an enigma. 

Erdogan seems to have all of the principles of a seismograph or a weathervane. His recent actions after the attempted coup are hardly reassuring to his NATO and other allies.