The year 2019 will probably be a pivotal year for Turkey in terms of Defense. In October, it is due to receive its first S-400 systems acquired from Moscow. In November, as Defense Minister Hulusi Akar has just recalled, she hears receive its first F-35A, in accordance with the contract signed with Lockheed and the American authorities.
However, the American authorities seem firm on the fact that it will be one or the other, but not both. But threats of a defense embargo on Turkey, as well as economic sanctions under the CAATSA law, seem to have less and less effect on President Erdogan. In addition, the more the situation progresses, the more a retreat of the Turkish president as of the American president would appear like a diplomatic snub, with significant consequences on the public opinions.
For the moment, the Turkish authorities are playing the rope of "good faith", recalling that the country fulfills all its commitments, towards NATO as well as towards the F-35 program, and bears responsibility for the acquisition of S-400 on NATO's withdrawal of Patriot batteries deployed at the start of the Syrian crisis. This narrative seems to correspond to the hypothesis of a desire by the Turkish authorities to move towards leaving NATO, without publicly taking responsibility for it.
However, a break with Turkey's ban can only be considered economically by a rapid and significant rapprochement with Russia or China, or even both, so as to represent the 3rd pivot of an alliance which does not say its name, which would cause massive geopolitical upheavals in the Mediterranean as well as in the Caucasus and the Middle East.