Can Turkey be reeled back in as a trusted NATO partner? A growing chorus of policy-makers and foreign-policy analysts fear it can’t.

The threat this week by Turkey’s President Recep Tayyip Erdogan to launch a military incursion into Kurdish-majority areas in northern Syria is setting the stage for yet another fierce dispute between Ankara and the rest of NATO — including the U.S., which partnered with Syrian Kurds to rout the Islamic State terror group.

Erdogan’s warming ties with Russia’s Vladimir Putin and his purchase of an advanced Russian air-defense system — as well as his pursuit of strategies in Syria that conflict with those of other NATO partners and his support for Islamist causes— are straining Turkey’s ties with the West to the point of rupture, say analysts.

Pentagon officials also have expressed frustration with signs of an Erdogan rapprochement with Iran.

FILE - Presidents Hassan Rouhani of Iran, Recep Tayyip Erdogan of Turkey and Vladimir Putin of Russia hold a joint news conference after their meeting in Ankara, Turkey, April 4, 2018.

The crisis in Turkish-NATO relations is now as grave as in 1974, when Turkey invaded the Mediterranean island of Cyprus. There’s no formal mechanism for a NATO member to be expelled from the defense organization. Nonetheless, in Washington and European capitals, talk is mounting among policy-makers and influential foreign-policy analysts about whether Turkey has any future in NATO and whether the time is coming for it to leave or for its membership to be suspended.

“It's time to throw Turkey out of NATO,” opined British newspaper columnist Con Coughlin, a commentator who often reflects the views of Britain’s intelligence establishment.

Last month, European Union foreign ministers suspended about $164 million in aid to Turkey and shelved talks on an aviation accord in retaliation for Turkish drilling and gas exploration in the waters off Cyprus. The island has been partitioned since 1974 between the ethnically Greek south and ethnically Turkish north.

The administration of northern Cyprus is recognized only by Ankara. The EU foreign ministers also asked the European Investment Bank to review lending to the country, which amounted to nearly $434 million in 2018.

The EU measures came just days after the first shipments arrived in Turkey of a Russian-made surface-to-air missile system to Turkey.

FILE - First parts of a Russian S-400 missile defense system are unloaded from a Russian plane near Ankara, Turkey, July 12, 2019.

President Erdogan shrugged off Washington's warnings that it would penalize Turkey for the purchase and went ahead with deal anyway. U.S. defense chiefs say the S-400 system the Turks bought is not compatible with NATO defenses and poses a potential threat to U.S. F-35 stealth fighter. Responding to the delivery of the Russian system, U.S. President Donald Trump said he would withhold sales of advanced F-35 jets to Turkey, but refrained from further sanctions.

Erdogan said Tuesday that he is confident Trump won’t allow ties between the two NATO allies to become captive to the dispute over Ankara's purchase of the S-400 defense system. Speaking to Turkish ambassadors gathered in Ankara, Erdogan said he remained committed to NATO.

“There is no concrete evidence showing the S-400s will harm the F-35s or NATO, nobody should deceive each other. Many NATO member states have purchased from Russia. We don't see this being turned into a crisis,” Erdogan said. “Turkey made a business decision for its security.”

Analysts say Erdogan is banking on Western leaders having to balance their disapproval of his foreign-policy steps, as well as their disdain for his increasingly authoritarian actions domestically, with their need for Turkish assistance to curtail migration and for help with counter-terrorism. But they say Erdogan risks miscalculating and that the host of serious issues now straining Turkey’s ties with the West is nearing the point of rupture.

An incursion into Kurdish areas of northern Syria would add considerably to the strains.

FILE - Turkish troops head to the Syrian border, in Karkamis, Turkey, Aug. 27, 2016.

The crisis has long been in the making. Since 2013 Erdogan has pulled against NATO and the West. He was indignant over the refusal by the U.S. and the EU to condemn the toppling by the Egyptian army of Egypt’s elected President Mohamed Morsi, an Islamist, and scolded the West for perceived double standards. He accused Israel of playing a role in Morsi’s ouster.

He turned increasingly cool to the idea of Turkey joining the European economic bloc, something the country has aspired to for half-a-century despite repeated rebuffs from some key European states including Germany. His chief negotiator with the EU said Turkey would likely never join, blaming the “prejudiced” attitudes of current EU members, and sneering the EU is in a “process of dissolution” anyhow.

In a Brookings Institution report last year, analyst Amanda Sloat noted the West has a “Turkey conundrum.” While it wanted Turkey to remain a NATO member, partly because it occupies an important geo-strategic space, “the country’s president is growing more authoritarian, using virulent anti-Western rhetoric, and making foreign policy choices contrary to the interests of the trans-Atlantic alliance,” she noted.

Erdogan, analysts and Western diplomats say, has proven himself in the past as master-manipulator of the West, astutely knowing when to pull back and when to shrug off Western warnings, betting that what Turkey has to offer the West, including the important NATO air-base at Incirlik in the south of the country, would persuade the U.S. and Europeans to overlook his warming ties with Russia.

FILE - Turkish soldiers carry a huge national flag and a portrait of Mustafa Kemal Ataturk, founder of modern Turkey, during a military parade in Ankara, Turkey, Aug. 30, 2015.

But how long can that continue? Doug Bandow, an analyst with the Cato Institute, a Washington think tank, noted this week that “the only serious potential security threat to Europe today is from Russia. Yet Turkey cannot be trusted to take NATO’s side in a conflict.” He argues NATO has little choice but to suspend Turkey’s membership, as Ankara’s foreign policy now diverges so greatly from that of the Western states. “In practice, Turkey has already been ‘lost' to the alliance,” he argues.