Lockheed Martin F-35 Photographer: Carla Gottgens/Bloomberg (Bloomberg)

Understanding Turkey’s rollercoaster relations with the U.S. requires a grasp of advanced military hardware. The Turkish government is on the brink of buying Russia’s S-400 missile-defense system, angering President Donald Trump’s administration, which argues that integrating it with NATO’s second-largest army could help Moscow gather critical intelligence. In response, the U.S. has threatened to impose sanctions on Turkey and eject it from the U.S. F-35 fighter jet program. Turkish leader Recep Tayyip Erdogan has relied on a rapport with Trump to resolve other bilateral disputes. But with the U.S. Congress sticking to its guns in opposing the S-400 deal, there’s a high risk of punishments that could plunge Turkey into renewed economic turmoil.

1. Why is the U.S. so opposed to the deal?

The S-400, also known within NATO as the SA-21 Growler, has advanced radars and isn’t compatible with NATO technology. Its deployment in Turkey would mark a further advance in Russian President Vladimir Putin’s efforts to engineer a bigger role in the Middle East. Chief among U.S. concerns is that the Russian system could be used to collect intelligence on the F-35’s stealth capabilities. There’s history here. Turkey is home to the Incirlik Air Base, used for U.S. operations against Islamic State and, decades before that, the main operating location for the U.S. U-2 spy plane -- until American pilot Francis Gary Powers was shot down over the Soviet Union in a famous incident in 1960.

2. What explains Turkey’s determination to press ahead?

Erdogan says Turkey’s western allies failed to provide his country the necessary defense against missile threats from neighboring Iran, Iraq and Syria. The U.S. balked for years at selling Turkey its Patriot air defense system and sharing its technology at the same time. In December, the State Department notified Congress that it had proposed allowing the sale, a gambit seemingly designed to get Erdogan to scrap the S-400 deal. Turkey wasn’t moved, citing uncertainty over the transfer of U.S. technology and the timetable for delivery. Its reluctance also reflects Turkey’s desire for an increasingly independent role in regional policies and for economic ties with Russia, which ships natural gas, lots of tourists and agricultural goods to Turkey.

3. How else has Turkey asserted military independence?

Turkey’s defense industry developed its own unmanned drones, ending a dependence on Israeli ones. “Turkey is sick of being a market,” Defense Minister Hulusi Akar said. “We will become a producer, too.” Turkish military spending surged 65 percent between 2009 and 2018, according to the Stockholm International Peace Research Institute, which researches global arms expenditure. Last year, its spending rose at the fastest pace among the world’s top 15 arms purchasers to $19 billion.

4. How far might the U.S. go?

The U.S. warned that Turkey faces expulsion from Lockheed Martin Corp.’s F-35 program. Turkish companies were set to produce about $12 billion in parts for the jet, and the Turkish air force planned to buy about 100 of the planes. Deliveries of F-35 equipment to Turkey have been suspended. U.S. Secretary of State Michael Pompeo signaled that the size of the S-400 purchase -- estimated at more than $2 billion -- could also trigger sanctions against Turkey under the U.S. Magnitsky Act and other legislation that allows penalties on entities doing business with parts of the Russian state. The last time the U.S. sanctioned some members of the Turkish government, over the arrest of an American preacher, it amplified the problems haunting the Turkish economy. An ensuing collapse in the value of the currency hastened the country’s first recession in a decade.

5. What else have the U.S. and Turkey been sparring over?

Plenty. Their six-decade alliance has been strained by U.S. support for a Syrian Kurdish militia that Turkey considers a foe, and Washington’s refusal to extradite Fethullah Gulen, the Turkish cleric living in exile in Pennsylvania whom Erdogan accuses of orchestrating a failed 2016 coup. Turkey’s detention of the American pastor, Andrew Brunson, as well as employees of U.S. diplomatic missions in Turkey on allegations of involvement in the attempted putsch or terrorism-related charges, inflamed things further. Turkey wants the release of Mehmet Hakan Atilla, former head of international banking at Turkish state-lender Halkbank convicted in a New York court in 2018 for participating in a scheme to help Iran evade U.S. sanctions. The U.S. opposes Turkey’s trade relations with Nicolas Maduro’s government in Venezuela.

6. Is there a path to a compromise?

Turkey believes it has valuable bargaining chips, including an early-warning radar at Kurecik, a critical part of NATO’s ballistic-missile defense capabilities, and the base at Incirlik. Erdogan has taken the case for buying the Russian S-400s directly to Trump, in a last-ditch effort to prevent or at least soften any sanctions. “Turkish-American ties can’t be disregarded,” Defense Minister Akar said in Washington.

To contact the reporter on this story: Selcan Hacaoglu in Ankara at shacaoglu@bloomberg.net

To contact the editors responsible for this story: Leah Harrison Singer at lharrison@bloomberg.net, ;Onur Ant at oant@bloomberg.net, ;Benjamin Harvey at bharvey11@bloomberg.net, Mark Williams

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