Witnesses Tell Senate Turkey’s S-400 Purchase Reflects Erdogan’s Personal Calculus, Risks NATO Integration

Senator Mitt Romney asked witnesses to explain why Turkey purchased the S-400 and whether Ankara miscalculated the consequences for its NATO ties and F-35 production. Mr. Brzezinski said the decision is rooted in President Recep Tayyip Erdogan’s personal calculus: he characterized the purchase as "a dangerous flirtation" with Russia that integrates Russian systems into Turkish forces and intelligence.

Why it matters: Experts warned the S-400 is more than a weapons purchase. Mr. Brzezinski said it "is extremely significant because he's basically not just buying a system, but he's integrating into the core of the armed forces, the Turkish armed forces, Russian intelligence," a step that complicates interoperability and intelligence-sharing with NATO.

Dr. Polakova highlighted Russia’s leverage: Moscow can influence Turkish domestic politics through refugee flows or by disrupting tourism, which she said can quickly damage Erdogan’s standing. "Russia has a huge amount of leverage over Turkey...Russia's positions in Syria could turn up another refugee wave," she said.

Mister Townsend traced the purchase to prolonged bargaining over the U.S. Patriot missile sale and technology transfer, saying Turkey explored other options, including a Chinese system, before turning to Russia: "He threw into that...the point that he has options," Townsend said.

Taken together, witnesses described the relationship as personality-driven and transactional rather than a durable alliance shift. They cautioned that normalization of U.S.-Turkey ties may require political change in Ankara and long-term diplomatic work; no immediate policy remedy was proposed during the exchange.

Next steps: The committee received testimony but did not take formal action. Witnesses recommended sustained diplomacy, clearer allied messaging, and monitoring of how (or whether) the S-400 systems are actually used.