The once solid U.S.-Turkish relationship has foundered on miscalculations, grievances, and increasingly divergent worldviews.

When Secretary of State Rex Tillerson arrives in Ankara on Thursday, he will find Turkey unrecognizable as the ostensibly Muslim democracy and close ally that U.S. officials once held up as a model for the Islamic world. After a controversial constitutional referendum last year, President Recep Tayyip Erdogan is poised to complete his long transformation of Turkey from a raucous — if imperfect democracy — to an autocracy, one ruled by caprice and fear. Across a wide boulevard from the U.S. Embassy in Ankara, Tillerson will find that the Turkish parliament building still bears the scars of the 2016 attempted military coup that pro-government media blame squarely on the United States, a narrative that Erdogan has used to whip up nationalism and anti-Americanism to unprecedented levels.

Still wielding the emergency powers established after the coup, Erdogan has fired or suspended roughly 130,000 judges, bureaucrats, academics, and journalists from their jobs for alleged connections to a coup involving a few hundred troops. An estimated 45,000 Turks have been arrested and held indefinitely in “pre-trial detention,” many of them political opponents. Political and civil rights are so shackled that for the first time the civil society group Freedom House classified Turkey as “not free” last month in its annual “Freedom of the World” report.

Erdogan’s slow motion strangulation of democracy, however, will not top Tillerson’s contentious agenda with his Turkish counterpart. A pronounced eastern tilt in Ankara’s strategic orientation has seen this erstwhile NATO ally agree to purchase an advanced Russian air defense system, and attend Moscow-sponsored talks on the future of Syria that excluded the United States. A recent trial of a Turkish-Iranian gold trader in New York revealed that top ministers in Erdogan’s government were involved in a lucrative scheme to help Iran circumvent sanctions over its suspected nuclear weapons program to the tune of an estimated $100 billion.

Meanwhile, Turkey’s campaign of intimidation against critics at home and abroad has included the arrest of U.S. consulate workers and two U.S. citizens in Turkey; the issuance of arrest warrants targeting U.S. critics at think tanks and universities in this country; and death threats by social media trolls close to the Ankara government. Last year Erdogan’s body guards viciously attacked peaceful demonstrators in Washington, prompting the D.C. police to issue arrest warrants for a dozen members of Erdogan’s security detail.

“Much like Iran, Turkey is increasingly becoming a ‘klepto-theocracy’ where government leaders and family members profit handsomely from their positions, and both governments are united by an Islamist worldview that stands in opposition to the West,” said Aykan Erdemir, a former Turkish parliamentarian and senior fellow at the Foundation for the Defense of Democracies in Washington, D.C. Erdemir’s own criticism of Erdogan has led the Turkish government to seize his assets and issue a warrant for his arrest. “That’s the kind of tragedy we’re watching unfold.”

Friend of My Enemy

Remarkably, even those yawning fissures in a once solid U.S.-Turkish relationship will not top Tillerson’s agenda in Turkey. That spot is reserved for a military offensive the Turkish military recently launched targeting Kurdish forces in the northern Syrian city of Afrin. Erdogan has publicly promised to expand that offensive to nearby Manbij, where U.S. forces involved in the anti-ISIS campaign operate alongside Kurdish allies that Ankara considers terrorists. Erdogan recently called U.S. support for the Syrian Kurdish forces proof that Washington “had designs against Turkey.” The Turkish offensive now raises the once unthinkable prospect that U.S. and Turkish military forces could find themselves on opposing sides on a Syrian battlefield.

“Look it’s difficult. The rhetoric is hot. The Turks are angry, and this is a difficult time to do business,” said a U.S. official briefing reporters last week on Tillerson’s visit. “But it’s our belief that there are still some very fundamental underlying shared interests.”

Steven Cook is senior fellow for Middle East and Africa studies at the Council on Foreign Relations, and author of False Dawn: Protest, Democracy, and Violence in the New Middle East. “A lot of U.S. officials still want to believe that Turkey is a stabilizing influence in the Middle East, but its destabilizing actions are getting harder and harder to ignore,” he said. Cook notes that Turkey regularly whips up anti-Israeli sentiments in the region; backed Sunni jihadists associated with Al Qaeda and other Islamist extremist groups for years in the sectarian Syrian civil war; and has moved increasingly close to Russia and Iran.

With last year’s close and questionable vote on the constitutional amendment, Erdogan’s assault on the institutions of Turkish democracy could extend another fifteen years, Cook notes, even as the Turkish leader continues to stoke anti-Americanism. “Erdogan could ultimately be in power for nearly 30 years, meaning whole generations of Turks will have been reared on his narrative that the United States is a bad actor, which is deeply corrosive to the relationship,” said Cook. “And after each outrage Washington officials either look the other way or wonder aloud why Turkey is not acting like a NATO ally anymore. Along with structural problems in the relationship, this dynamic is making it hard to imagine that the United States and Turkey will ever be close allies again.”

A Once Strong Alliance

Turkey’s position as a strategic U.S. partner and NATO ally owes much to geography. During the Cold War, Turkey was the southern anchor of the Western alliance and a bulwark against Soviet expansion in the region. The deal to defuse the 1962 Cuban Missile Crisis, for instance, required that the Soviets withdraw nuclear missiles from Cuba in exchange for the United States withdrawing its missiles from Turkey.

A-10s at Incirlik Air Base, Turkey

Even after the end of the Cold War and throughout the 1990s, Turkey’s strategic location and the massive NATO air base at Incirlik in southern Turkey proved vital. Incirlik was the epicenter of Operation Northern Watch, the U.S.-led mission to enforce a “no fly” zone over northern Iraq following the 1991 Persian Gulf War. U.S. intelligence agencies reciprocated in 1999 by helping Turkey capture the Kurdish rebel leader Abdullah Ocalan, leader of the Kurdistan Workers Party (PKK), which had fought for 15 years for an autonomous Kurdish region in southern Turkey. Both the U.S. and Turkey have designated the PKK a terrorist group, and its insurgency inside Turkey has cost nearly 40,000 lives. U.S. diplomats also championed Turkey’s candidacy for long-sought membership in the European Union.

After the September 11, 2001 terrorist attacks launched a “global war against terror,” the Bush administration found in the rise of Erdogan and his openly Islamist Justice and Development Party a useful model of a supposedly moderate Muslim regime that had reconciled the tensions between Islam and democracy.

David Deptula

“I realize that some of the undemocratic steps Erdogan has taken are of concern from a political standpoint, but the United States and NATO should take the longer view and realize that Turkey remains of enormous strategic importance,” said retired Air Force Lt. Gen. David Deptula, who previously commanded all U.S. air operations in the Middle East, and also led Operation Northern Watch out of Incirlik. As the former Joint Task Force commander for Northern Watch in the late 1990s, Deptula briefed a slide that showed the range and radius of an F-15E fighter-bomber flying out of Incirlik. “Roughly three quarters of the significant conflicts that have taken place since World War II were within that F-15’s flying radius, which gives you an idea of how important Turkey remains as a NATO ally,” he said. “Despite our political differences, the military-to-military relationship between NATO and the Turkish general staff remains good.”

Parting Ways

Like many partnerships gone bad, U.S.-Turkish relations have slowly soured. Bush administration officials were furious at Ankara for not allowing the 4^th Infantry Division to launch a planned northern front from Turkish soil, for instance, as part of its 2003 invasion of Iraq. Equally indignant Turkish officials note that their dire warnings about the destabilizing impact of the Iraq invasion on the region ultimately came to pass, including a resurgence of PKK violence and a flood of Iraqi refugees into Turkey. (The Turkish embassy in Washington did not comment for this).

After Turkey sided with Syrian protesters during Arab Spring demonstrations against strongman Bashar al-Assad in 2011, Erdogan was furious that the Obama administration refused to intercede as Syria descended into a civil war that sent more than three million Syrian refugees into Turkey. The Obama administration even failed to use military action o enforce its own stated “red line” against Assad’s use of chemical weapons on Syrian civilians.

For its part, Washington strongly objected when Turkey responded by opening its borders and turning a blind eye to Sunni jihadists who used its territory and flowed into Syria to fight Assad’s forces, often joining groups such as the Al Qaeda-linked Al Nusra Front, and the Islamic State of Iraq and Syria (ISIS). When the Obama and Trump administrations finally did send small numbers of U.S. “train and assist” troops to Syria to counter ISIS, Ankara was upset that they chose as local proxies the Syrian Kurdish fighters of the YPG group, an offshoot of the PKK Kurdish group  based in northern Iraq that both nations consider terrorists. U.S. military leaders got around the linkage by placing the Syrian Kurdish fighters under the wider umbrella of Syrian Democratic Forces that include some Arab militias.

“Both the Obama and Trump administrations made the decision that they were not going to send U.S. combat troops back to the Middle East to intervene directly, and that forced the U.S. military to make a tactical and supposedly temporary alliance with the Kurds of the YPG. Each time the U.S. extends that temporary alliance the Turks get more worried,” said Soner Cagaptay, director of the Turkish Research Program at the Washington Institute for Near East Policy, and author of The New Sultan: Erdogan and the Crisis of Modern Turkey.

With the Erdogan brand increasingly defined by political Islam and nationalism, Cagaptay noted, the Turkish leader is bound to ratchet up anti-American and anti-Kurdish rhetoric to excite his base in anticipation of elections scheduled for next year. “That puts Erdogan and the Turks on a collision course with the Kurds of the PKK and YPG, with the United States in the middle,” he said. “So this triangulation Washington is conducting in allying itself both with Turkey and the Syrian Kurds is coming to a head, and may no longer be sustainable.”

Turkey’s 9/11

If the United States and Turkey eventually split over their irreconcilable differences, the single most polarizing event will likely be the attempted military coup on the night of July 15, 2016. During the attempt to overthrow Erdogan, a group of rogue soldiers used U.S.-supplied Turkish F-16 fighter aircraft to bomb and strafe the parliament building, and more than 240 mostly unarmed civilians were killed confronting the soldiers. On the night of the coup Turkish national police entered Incirlik and arrested a Turkish general there suspected of complicity. For nearly a week the power and flight operations were shut down at the base, which houses an arsenal of U.S. tactical nuclear weapons.

The Turkish public was so traumatized by the events of July 15 that many refer to it as “Turkey’s 9/11.” When the smoke cleared, Erdogan emerged in a vengeful mood. The coup mastermind, he insisted, was former ally turned chief political rival Fethullah Gulen, an Islamist cleric living in exile in Pennsylvania with a U.S.-government issued Green Card. The failure of the U.S. Justice Department and courts to extradite Gulen has cast a dark shadow over U.S. – Turkish relations ever since.

Eric Edelman is a former undersecretary of Defense for Policy, and U.S. ambassador to Turkey in the Bush Administration. “Erdogan has created this extremely powerful political movement under the banner of ‘Islamo-nationalism,’ and he feeds it by constantly stirring up anti-American sentiment that excites his base. In that sense Turkey is no longer interested in acting like a normal ally,” he said in an interview. The response of successive U.S. governments has been to ignore Erdogan’s bad behavior and look the other way, he said, because Incirlik makes the U.S.-Turkish relationship too big to fail.

“Now we’re seeing the moral hazard of that policy because, if something is not done to change the trajectory of our relationship, U.S. and Turkish troops could very well end up shooting at each other in Syria,” said Edelman. “Anyone who tells you the relationship could never get that bad doesn’t have a lurid enough imagination, because 30 years in government taught me that things can always get worse.”