In the study, it was aimed to examine the events that started in Cyprus and led to the first great rupture in the alliance relations between Turkey and the United States of America, which was following a positive course in the aftermath of the Second World War, and the changed perception of the USA in Turkey following the correspondence recorded in history as "the Johnson Letter." Turkey, which attempted to be included in the Western bloc in order to eliminate the threat from the Soviet Union that emerged right after the end of World War II and needed the support of the USA in this regard, shaped its foreign policy on a single axis based on dependence in line with the wishes of its allies as stipulated by the conditions of the alliance after its joining the NATO. However, the events that started in Cyprus forced Turkey to face the reality. Turkey, which had to deal with Cyprus due to its strategic importance and the future of a considerable number of Turks living on the island, wanted to carry out military intervention in the island by using its legitimate right stemming from the international law in order to prevent the assimilation policies of the pro-Greece Greek administrators. The attempt to intervene led to a great rupture in Turco-American relations. The letter written by US President Lyndon B. Johnson in order to prevent a potential military intervention of Turkey in the island created a huge shocking effect in the administration of Turkey. Both the objection of its allies, which Turkey saw as friends, to the authority that Turkey wanted to use in a matter it was right about and given to it within the scope guarantor agreement in order to prevent the escalating violence on the island and the clear statement that its allies would not help Turkey and leave it on its own in case the Soviet Union initiated an attack on Turkey despite its being under the umbrella of the NATO are important in that these facts showed Turkey how wrong it was to shape its foreign policy on a single axis. The relations that were believed to be proceeding in a friendly and allied relationship between the governments until the Johnson letter was now going through a confidence crisis, and the letter irreversibly destroyed the sympathy for the USA in the eyes of the public as it was thought to prevent the intervention aimed at Cyprus. By screening the news published in the national press in addition to the written primary resources, the document analysis method was used in the study.

Cyprus, Turkish foreign policy, The United States of America.