Not a Divorce but a Defense Decoupling: What’s Next for the U.S.-Turkish Alliance

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After decades of speculation about the future of the U.S.-Turkish alliance, Washington and Ankara have finally reached a fork in the road. The day after Turkish President Recep Tayyip Erdoğan announced plans to deepen defense cooperation with Russia, his government formally submitted a request to the United States for 40 new Block 70 model F-16 aircraft and upgrade kits for 80 F-16s already in service with the Turkish Air Force. The U.S. Congress may well block the sale. And even if it goes through, Erdoğan may well decide to buy more Russian weapons anyways.

This impasse was the inevitable result of Ankara’s 2017 decision to purchase the Russian S-400 air defense system and Washington’s subsequent decision to impose sanctions and remove Turkey from the F-35 fighter program. As a result, the Turkish Air Force faces a serious issue in the near future. Ankara remains steadfast in its commitment to deploy the S-400, a system that Washington and major NATO allies have deemed a threat to Western tactical aviation. Absent a compromise on the deployment and location of the S-400, Ankara could be left without a fighter to replace aging F-16s. Turkey has made clear that it intends to develop its own fighter, dubbed TF/X, but the project is marred by issues with engine procurement and, at best, will not be produced at scale until the mid-2030s.



In the meantime, the Turkish government has sought to leverage its ties with Russia to coerce Washington into making concessions on the F-16 sale. In late September, following his visit to New York for the United Nations General Assembly, Erdoğan expressed his irritation with U.S. President Joe Biden. He accused Washington of supporting terrorists in Syria, and suggested that the United States could not be trusted to provide the equipment to upgrade and sustain Turkish F-16s. As part of this effort, Erdoğan then travelled to Sochi, Russia in late September, where he met with Russian President Vladimir Putin. It was after this meeting that he announced the two countries could deepen defense cooperation to include work on fighter engines, submarines, and rocket motors. Erdoğan has also signaled that Ankara may, in fact, push ahead and import a second S-400 regiment from Russia.

The United States has an interest in selling Turkey these F-16s. The Turkish government is a member of NATO and ancillary tensions over Syria should not negatively impact the sale of fourth-generation aircraft. But with trust so badly broken, it is unwise for Ankara to assume that U.S. policymakers will sign off on the export over concerns about “losing Turkey.” Playing the Russia card may not have its intended effect. The reality is that whatever Washington does, the United States and Turkey are rapidly reaching the last stage in their defense industrial decoupling. Legacy cooperation is now ending in favor of an autarkic Turkish effort to develop indigenous systems and find non-U.S. suppliers.

The S-400 Impasse 

Turkey’s cooperation with American defense firms is not as easy as it once was. In 2017, the U.S. Congress responded to Russia’s election interference by passing the Countering America’s Adversaries Through Sanctions Act. This legislation placed sanctions on Russia, but also threatened sanctions against third countries that purchased weapons from Russian state-owned defense industries. Turkey met the significant-transaction threshold when it purchased the S-400 missiles and then received the system in July 2019. But the Trump administration delayed imposing the sanctions. The delay prompted speculation that he and Erdoğan were enmeshed in an authoritarian bromance, wherein Erdoğan’s autocratic personality won over an equally dictatorially minded U.S. president. There is some truth to this. Then-President Donald Trump, according to author interviews with U.S. officials, would often quip, “I always like the tough ones,” during and after phone calls with the Turkish leader. The delay in imposing sanctions, however, was a pyrrhic victory for Turkey.

Congress responded to Trump’s inaction in the National Defense Authorization Act for Fiscal Year 2020 by tightening the language about sanctions and limiting the role of the executive in the process. Section 1245 clearly underscores the mood of Congress about future arms sales to Turkey. The text states that lifting sanctions or transferring the F-35 cannot take place unless Ankara “no longer possesses the S-400” and “provides credible assurances” that it will not procure the S-400. During the confirmation testimony for former Senator Jeff Flake, President Biden’s selection to be the next Ambassador to Turkey, Chairman of the Senate Foreign Relations Committee Robert Menendez went further, saying, “I do not see any new sales of (US) weapons systems in Turkey, unless there is a dramatic change in the conduct of the S-400s.”

This expansive view of U.S. sanctions could have been avoided, had Turkey and the United States reached a compromise on the S-400 during Trump’s term. On the S-400, the Trump administration suggested a compromise to avoid sanctions: The missile system would have to be kept in storage and not activated. This compromise would not have allowed Turkey to regain access to the F-35, but could have avoided the imposition of sanctions and eased the Congressional blockade on arms exports. Instead, the Turkish government chose to test the system in late October 2020, which led to the Trump administration to sanction Turkey in its final months in office. By delaying, the Trump administration pushed Congress to tighten language about sanctions and to block foreign military sales to Turkey.

The Future of the Turkish Air Force 

The Turkish Air Force suffered a serious crisis after the failed July 2016 coup attempt. The follow-on purges of officers had a deleterious effect on the pilot-to-aircraft ratio in the air force. Combined with this, the Turkish F-16 fleet has been used extensively for border patrol since the start of the Syrian civil war, as well as during counter-Kurdistan Workers Party (or PKK) missions since 2015, and in support of Turkish operations in Syria’s Idlib in 2020. The Turkish F-16 fleet is large, but aging. Ankara had intended to replace its entire legacy F-4 fleet and an unspecified number of F-16s with 100 F-35As.

The loss of the F-35 upended Turkish defense planning and undermined key assumptions the air force had made about the future of its fighter fleet. In this sense, the current effort to replace the F-35 with older models makes sense: The Block 70 fighter shares certain sensor characteristics with the F-35 and could help sustain the air force for the decade or more needed to build a capable indigenous fighter. The Turkish government has also suggested that it may purchase fighters from Russia. This approach makes little economic sense, given that the entirety of the Turkish Air Force logistics and maintenance operations are tethered to the F-16 and other U.S.-origin fighters. Despite this, Turkish political elites could decide investing further in bilateral relations with Russia has benefits beyond narrow concerns about military sustainment and logistics.

The Turkish letter of request for the F-16 purchase and upgrade kits is the first indication that Ankara is making concrete preparations for a future without the F-35. To date, Ankara has suggested that it would move to rely more heavily on a domestically produced fighter dubbed the TF/X. The program is ambitious and has stumbled because of troubles procuring an engine. Ankara has approached Rolls Royce, but the two sides failed to reach agreement on technology sharing over concerns that a Turkish firm owned in part by a Qatari defense firm would gain access to sensitive intellectual property. In the years after, Ankara has sought to develop its own engine for eventual integration with the TF/X, while also quietly continuing outreach to Rolls Royce. The first TF/X is slated to use the F110 engine, which powers the F-16, and which is also locally assembled in Turkey in a co-production arrangement with General Electric.

The Turkish political elite could decide that the benefits of breaking free from Washington outweigh the short-term problems caused by decoupling from the United States. This would accelerate Ankara’s ongoing efforts to find alternative suppliers of air and cruise missile engines for the unmanned and rotary wing programs currently in development. Finding alternate suppliers would also sidestep American restrictions on the re-export of Turkish-made defense products that include U.S.-origin equipment. This approach could shield Ankara’s defense industry during times of tensions with Europe and America, which have been ongoing for close to decade.

In the meantime, though, the removal of Turkey from the F-35 program has had a series of secondary effects that the Turkish government has to grapple with. The Turkish request for 40 new F-16s is a clear indication that, when forced to choose, Ankara is eager to continue to operate an American-origin fighter. The loss of the F-35 also adds urgency to the TF/X project. As of now, it is Ankara’s only option to field a fifth-generation fighter. This project has been marred by delays, and it is unclear if this program will ultimately result in the manufacture of large numbers of Turkish-made fighters. Hence the current request before Congress.

What Now?

The U.S. Congress has made clear that future arms exports depend on resolving the S-400 issue. The Biden administration has, since taking power, shown deference to congressional prerogative on this issue. The likelihood for stalemate in the U.S. system is high. Turkish officials would be wise to seriously consider a compromise on the S-400. The future of the Turkish Air Force is murky and a single S-400 regiment is not worth the problems it will cause.

Ankara, however, may think differently, and prefer to turn back to Russia. Turkey’s original purchase of the S-400 made no sense — Ankara could have purchased U.S. or European alternatives and had ample warnings that procuring this Russian system would lead to sanctions and the loss of the world’s only fifth-generation fighter built for export. But Turkish civilian leadership defied Washington in spite of these consequences, and Turkey now has an operational S-400 at Murted Air Force Base.

Put simply, both sides should compromise. But both sides should also be prepared for the fact they probably won’t.



Aaron Stein is the director of research at the Foreign Policy Research Institute and the author of the forthcoming book The US War Against ISIS: How America and its Allies Defeated the Caliphate.

Image: U.S. Air Force (Photo by Staff Sgt. Jason Allred)