“Turkey has been an American Ally since 1952,” wrote the senators. “For decades Turkey worked to build a society open to people of all faiths, and stood against Russian aggression. But a valuable ally has drifted.”

The S-400 systems Turkey purchased were “designed to shoot down the F-35,” the next-generation stealth fighter jet developed by the United States, the pair wrote.

Turkey was part of the F-35 program and was penciled in to purchase 100 of the jets, but was removed over the S-400 purchase last year.

Many have warned Ankara of consequences, they said, noting that “the president should now follow the law and levy sanctions against Turkish entities,” Ahval reported.

There is bipartisan support in both the Senate and the House for sanctions, and the National Defense Authorization Act (NDAA) was recently finalized with a clause calling for sanctions on Turkey under the Countering America’s Adversaries Through Sanctions Act (CAATSA).

U.S. President Donald Trump gave Turkey “every opportunity to cooperate with NATO,” they said.

The senators urged countries of the world to “consider who is a better trade partner: The U.S., with more than 20% of the world’s economy, or Russia, with an economy smaller than the economies of some U.S. states,” when choosing who to ally with.

According to the two Republican senators, punishing Turkey via sanctions “would be a clear warning,” whereas “a failure to follow through would send the message that the U.S. isn’t willing to make hard decisions.”

The Turkish government has “invited sanctions on an already struggling economy. It didn’t have to be this way,” said the pair.

“The U.S. has an obligation to protect American interests from threats from Iran, Russia and North Korea. Turkey needs to understand the consequences of its decisions,” they added.

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