Will President Biden give an audience to President Erdogan during next week’s summit at Washington, even as Ankara’s ties with America’s adversaries and Islamist terrorists grow?

Turkey has long been considered an indispensable member of the North Atlantic Treaty Organization. Yet, critics now say that Mr. Erdogan’s Ankara is turning against the alliance and violates the organization’s underlined values. 

The alliance and Mr. Biden must change their attitude, an American Enterprise Institute senior fellow, Michael Rubin, says. “NATO doesn’t fully grasp the image problem they have,” he tells the Sun. “If they can’t stand up to Erdogan, why should Putin believe they’d stand up to him?”

After Mr. Erdogan opted for Russian-made S-400 air defense systems instead of the American-made equivalent widely used by NATO, Washington canceled Turkey’s participation in the fifth generation of the F-35 fighter jet program.

As Turkey also became a money laundering hub for Russian oligarchs, Washington also held up an Ankara 2021 order of F-16 fighter jets. Mr. Erdogan raised the stake by refusing, along with Hungary, to confirm Sweden’s accession to NATO.

Only after a series of negotiations between Washington  and Ankara, Mr. Erdogan finally agreed to remove his objection to Sweden’s NATO membership. In return, Mr. Biden approved the F-16 sale. 

Meanwhile Turkey is increasingly emerging as a state sponsor of Islamist terrorists. Following the horrific October 7 Hamas assault, Mr. Erdogan has ratcheted up attacks on Israel. Turkey is now as useful to Hamas as the Islamic Republic of Iran. It is a leading backer of an American- and European Union-designated terrorist organization. 

In April Mr. Erdogan fêted the Doha-based Hamas chief, Ismail Haniyeh, at Istanbul. In May, Ankara announced a full trade embargo on Israel, even as some of Turkey’s largest companies have products they manufacture exclusively for use in the Israeli market.

Addressing members of his Justice and Development Party, or AKP, recently, Mr. Erdogan called Prime Minister Netayahu a “vampire,” adding “America, this blood is also on your hands. Heads of the states in Europe, you have become complicit in Israel’s vampirism because you remained silent.” 

Over the weekend an El Al commercial plane flying to Tel Aviv from Warsaw made an emergency landing at Antalya, Turkey, after a passenger on board became ill. Crews on the ground refused to refuel the plane, forcing passengers to spend hours on board before the plane finally took off to Rhodes, Greece, for refueling. 

Mr. Erdogan is widely believed to have personally ordered the denial of services to the Israeli plane. “Once things escalated at the airport, the Antalya bureaucrats likely pushed it up the presidential palace,” a former Turkish politician tells the Sun, asking for anonymity for fear of retribution.

The former politician noted that Israel was the first country to send rescue teams to Turkey when it suffered a devastating magnitude 7.8 earthquake last year. Whether or not Turkey violated international aviation rules by refusing services to an EL Al plane, “it certainly wasn’t paying Israel in kind,” he said. 

On Monday riots broke out near Turkey’s border with Syria, where local mobs attacked Syrian refugees. Ankara arrested rioters and Mr. Erdogan condemned the violence, blaming it on opposition parties. 

Rather than organized from above, the riots were “organic, xenophobic, racist attacks fueled by decades of Erdogan propaganda,” the former Turkish politician said. “People are angry at Erdogan’s policies and at the poor state of the economy. But they’re banned from criticizing the leader, so they scapegoat refugees instead.”

Back in April Ankara abruptly postponed Mr. Erdogan’s planned Washington visit and White House meeting with the president. No sufficient explanation was provided by either side. When he lands on American soil next week, will the Turkish president be considered an ally?

Turkey’s military is NATO’s second largest, behind America’s. Yet, would Mr. Erdogan allow his army to fight for NATO causes? Is the large U.S. Air Force air base at Incirlik still irreplaceable even as America has better ties with Greece and Cyprus than with Turkey? Could other Turkish-based NATO assets, like the radar early warning system at Malatya, be relocated?

The first thing the alliance leaders must do to decouple NATO from Turkey, is to “end the myth that Turkey is indispensable to the alliance,” Mr. Rubin says. Perhaps even before that, the White House brass could shun Mr. Erdogan and his entourage at next week’s summit.