In this research, the tensions and conflicting interests between the two allied countries Turkey and the USA sharing liberal values challenge the cooperation frame will be investigated by looking at their approaches during the S-400 and F-35 crisis. The objective of the study is to investigate the sides preferring different approaches for the solution of the issue regarding the S-400 and F-35 crisis between Turkey and the USA caused by the global developments resulting from the national security and interests between the years 2002-2020. In this frame, a qualitative research design with an explanatory/descriptive case study strategy was used. The data were collected through interviews and documents. The study concluded that the USA side chose to approach the problem by embracing sanctions and threatening with sanctions instead of solving the problem by negotiating with a liberal approach during the S-400 and F-35 crisis between two countries
Turkey - USA Relations, S-400 and F-35, Tensions