- Greece and Turkey have both asked to buy US-made fighter jets.
- Athens and Ankara have differing relationships with the US and may get different responses.
- That divergence may worsen the already fraught ties between the two NATO allies.
Turkey and Greece, two of NATO's most valuable but least friendly allies, are pursuing new US-made fighter jets, but their diverging relationships with Washington mean they might not both get what they want.
In June, Greece submitted a request to the US for the purchase of 20 F-35 stealth fighters with the option for 20 more jets in the future. The request comes as Athens's ties with Washington, especially their defense relationship, grow closer.
Turkey had already requested to buy new US-made F-16s and F-16 upgrade kits last year, but in July, US lawmakers approved an amendment making that purchase harder by requiring President Joe Biden — who has expressed support for the sale — to certify to Congress that it is essential to US national security.
Greece and Turkey's location next to each other in southeastern Europe, bordering the Black Sea and the Eastern Mediterranean Sea, makes them strategically important NATO members amid heightened tensions in those regions.
But their relationships with the rest of the alliance are heading in opposite directions, and their own longstanding rivalry may only worsen if one of them gets new jets and the other doesn't.
Congressional opposition
Greece and Turkey have a very poor relationship and have often come close to open conflict in recent decades.
The neighbors are at loggerheads over a number of issues, including ethnically divided Cyprus, opposing maritime claims in the Aegean and Eastern Mediterranean, and Turkey's recent challenge of the sovereignty of a number of Greek islands.
Turkey's relationships with other NATO members, particularly the US, have also deteriorated. Ankara was part of the F-35 program but was booted from it by the US for buying Russia's S-400 surface-to-air missile system, which the US believed could compromise Western platforms, including the F-35.
"Turkey has not endeared itself to the US of late," said Andrew Novo, a senior fellow with the Center for European Policy Analysis and a professor at the National Defense University.
"Numerous Turkish policies have been a cause for concern," Novo told Insider, citing the S-400 purchase, the blocking of Sweden's and Finland's bids for NATO membership, provocations against Greece and Cyprus, Turkish attacks on US-allied Kurdish fighters in Syria and Iraq, and Ankara's involvement in Libya's civil war.
US lawmakers have also expressed concern about erosion of democracy under President Recep Tayyip Erdogan.
"How do you reward a nation that does all of those things?" Sen. Bob Menendez, chairman of the Senate Foreign Relations Committee, told Politico in July. "I don't see it. Now, if they want to start changing their ways, that's a different story."
The House amendment regarding Turkey's F-16 request also requires Biden to describe steps being taken "to ensure that such F-16s are not used by Turkey for repeated unauthorized territorial overflights of Greece."
The amendment could be "a practical way to try and reign in Turkish military capabilities in order to constrain Ankara from becoming even more independent on the international scene in using its military," Novo said.
"It could be a useful bargaining chip against something more substantive that Washington would like from Ankara," he added.
Tense Aegean skies
Athens and Ankara frequently accuse each other of flying into the other's airspace. Their jets regularly engage each other over the Aegean and both sides have lost pilots and jets in those encounters.
"Greece acquiring F-35s is not something Turkey would like to see as it would provide Greece a superior combat aircraft platform," Novo said.
The Hellenic Air Force has a fighter fleet of nearly 200 aircraft, more than half of them F-16s. The Turkish fighter fleet is slightly larger and made up mostly of F-16s. This had created a rough parity, but the situation is now changing.
Greece is upgrading 84 of its F-16s to the latest Viper configuration and recently ordered 24 French Rafales, which are slightly more advanced than the F-16 but not as sophisticated as the F-35.
The Turkish Air Force on the other hand is still recovering from the 2016 attempted coup against Erdogan, which led to hundreds of its pilots being dismissed.
Participating in the F-35 program would have given Turkey an advantage over Greece's F-16s, Novo told Insider. But if Greece's F-35 request is approved, "it would certainly make Turkey think twice about challenging Greece in the skies" and would improve "Greece's deterrent capabilities significantly," he added.
The inability to upgrade and expand its F-16 fleet has led Turkey to explore alternatives.
Ankara is reportedly looking at Eurofighter Typhoons — a 4.5-generation jet like the Rafale — instead of advanced F-16s. Turkish Aerospace Industries, which is mostly state-owned, is working with British firm BAE Systems to develop the TF-X, a fifth-generation stealth aircraft scheduled to enter service in 2028.
Turkey is also developing the HÜRJET light combat aircraft in order to decrease its air force's reliance on the US.
The US has long sought to support Greece and Turkey and to contain their longstanding rivalry, viewing the two countries as an important bulwark in southeastern Europe.
While there are calls for the US to maintain its role as an even-handed mediator, the growing ties with Athens and increasing tension with Ankara appear to reflect a changing calculus in Washington.
Constantine Atlamazoglou works on transatlantic and European security. He holds a master's degree in security studies and European affairs from the Fletcher School of Law and Diplomacy. You can contact him on LinkedIn.