ANKARA, TURKEY - JULY 12 : First batch of equipment of S-400 missile defense system is being unloaded from a Russian Antonov AN-124 Ruslan transport aircraft at Murted Air Base in Ankara, Turkey on July 12, 2019 as S-400 hardware deployment started. Following protracted efforts to purchase an air defense system from the U.S. with no success, Ankara signed the supply contract in April 2017 to purchase the Russian S-400s. ( Mustafa Kamacı - Anadolu Agency )

ANKARA, TURKEY - JULY 12 : First batch of equipment of S-400 missile defense system is being unloaded from a Russian Antonov AN-124 Ruslan transport aircraft at Murted Air Base in Ankara, Turkey on July 12, 2019 as S-400 hardware deployment started. Following protracted efforts to purchase an air defense system from the U.S. with no success, Ankara signed the supply contract in April 2017 to purchase the Russian S-400s. ( Mustafa Kamacı - Anadolu Agency )

ANKARA, TURKEY - JULY 12 : First batch of equipment of S-400 missile defense system is being unloaded from a Russian Antonov AN-124 Ruslan transport aircraft at Murted Air Base in Ankara, Turkey on July 12, 2019 as S-400 hardware deployment started. Following protracted efforts to purchase an air defense system from the U.S. with no success, Ankara signed the supply contract in April 2017 to purchase the Russian S-400s. ( Mustafa Kamacı - Anadolu Agency )

ANKARA, TURKEY - JULY 12 : Trucks carry the first batch of equipment of S-400 missile defense system, unloaded from a Russian Antonov AN-124 Ruslan transport aircraft, at Murted Air Base in Ankara, Turkey on July 12, 2019 as S-400 hardware deployment started. Following protracted efforts to purchase an air defense system from the U.S. with no success, Ankara signed the supply contract in April 2017 to purchase the Russian S-400s. ( Mustafa Kamacı - Anadolu Agency )

ANKARA, TURKEY - JULY 12 : First batch of equipment of S-400 missile defense system is being unloaded from a Russian Antonov AN-124 Ruslan transport aircraft at Murted Air Base in Ankara, Turkey on July 12, 2019 as S-400 hardware deployment started. Following protracted efforts to purchase an air defense system from the U.S. with no success, Ankara signed the supply contract in April 2017 to purchase the Russian S-400s. ( Mustafa Kamacı - Anadolu Agency )

ANKARA, TURKEY - JULY 12 : First batch of equipment of S-400 missile defense system is being unloaded from a Russian Antonov AN-124 Ruslan transport aircraft at Murted Air Base in Ankara, Turkey on July 12, 2019 as S-400 hardware deployment started. Following protracted efforts to purchase an air defense system from the U.S. with no success, Ankara signed the supply contract in April 2017 to purchase the Russian S-400s. ( Mustafa Kamacı - Anadolu Agency )

ANKARA, TURKEY - JULY 12 : First batch of equipment of S-400 missile defense system is being unloaded from a Russian Antonov AN-124 Ruslan transport aircraft at Murted Air Base in Ankara, Turkey on July 12, 2019 as S-400 hardware deployment started. Following protracted efforts to purchase an air defense system from the U.S. with no success, Ankara signed the supply contract in April 2017 to purchase the Russian S-400s. ( Mustafa Kamacı - Anadolu Agency )

ANKARA, TURKEY - JULY 12 : First batch of equipment of S-400 missile defense system is being unloaded from a Russian Antonov AN-124 Ruslan transport aircraft at Murted Air Base in Ankara, Turkey on July 12, 2019 as S-400 hardware deployment started. Following protracted efforts to purchase an air defense system from the U.S. with no success, Ankara signed the supply contract in April 2017 to purchase the Russian S-400s. ( Mustafa Kamacı - Anadolu Agency )

ANKARA, TURKEY - JULY 12 : First batch of equipment of S-400 missile defense system is being unloaded from a Russian Antonov AN-124 Ruslan transport aircraft at Murted Air Base in Ankara, Turkey on July 12, 2019 as S-400 hardware deployment started. Following protracted efforts to purchase an air defense system from the U.S. with no success, Ankara signed the supply contract in April 2017 to purchase the Russian S-400s. ( Mustafa Kamacı - Anadolu Agency )

ANKARA, TURKEY - JULY 12 : First batch of equipment of S-400 missile defense system is being unloaded from a Russian Antonov AN-124 Ruslan transport aircraft at Murted Air Base in Ankara, Turkey on July 12, 2019 as S-400 hardware deployment started. Following protracted efforts to purchase an air defense system from the U.S. with no success, Ankara signed the supply contract in April 2017 to purchase the Russian S-400s. ( Mustafa Kamacı - Anadolu Agency )

ANKARA, TURKEY - JULY 12 : Russian Antonov AN-124 Ruslan, carrying the first batch of equipment of S-400 missile defense system, arrives at Murted Air Base in Ankara, Turkey on July 12, 2019 as S-400 hardware deployment started. Following protracted efforts to purchase an air defense system from the U.S. with no success, Ankara signed the supply contract in April 2017 to purchase the Russian S-400s. ( Mustafa Kamacı - Anadolu Agency )