Approved for public release; distribution in unlimited. / The dynamics in U.S.-Turkey relations in both 1964 and 2003 continued to be between a large global power and a medium regional power in the framework of a global threat that required regional cooperation. In both cases the priority of the global power was the fight against the global threat and this created expectations from the medium power ally in the region, who -in both cases- had its own reservations about the issue, considering its own national interests. The analysis of the 1964 Crisis shows that both U.S. and Turkey would have five main sources of influence over their foreign policy decisions leading to disagreement in 1964: the dynamics in the U.S. Turkish relations as one between a global power and a regional partner; domestic concerns of both countries; unaligned goals of the two parties; the international circumstances; and the influence of signaling failures and previous interactions. When we analyze the 2003 Crisis in light of these findings we see that all the main issues seem to be consistently relevant, though their effects might have changed slightly. Overall, both cases reveal that the above-mentioned five factors determine the outcome of interactions between large global powers and medium powers in the region. / 1st Lieutenant, Turkish Army