Sensing that its protracted efforts to purchase an air defense missile system from the ally U.S. was not heading towards success, Turkey in April 2017, signed a contract with Russia to acquire the S-400 anti-missile shield.
Opposing deployment of the Russian system, U.S. officials argued that would be incompatible with the NATO systems and expose its fifth generation, the state-of-art, F-35 jet, to possible Russian subterfuge.
Turkey, however, emphasized that the S-400 would not be integrated into the NATO systems, thus had no chance to pose any threat to the alliance or its armaments.
Turkey even asked for setting up of a commission to clarify any technical issues. But U.S. has, so far, not respond to this proposal.
The S-400 system is seen as one of the most advanced missile systems in the world, capable of tracking several targets simultaneously.
