On September 9th, the United States announced that it was planning a multi-billion dollar sale of 13 Patriot fire units, 72 PAC-3 missiles and a range of related hardware for ground-based air defence to Turkey. The decision, some commentators reasoned, was evidence that the US was turning to Turkey as an alternative base for the missile defence system (MDS) originally planned in Central Europe. Such assessments proved somewhat off the mark, however. What is on sale to the Turks (a system to protect Turkey against short- and medium-range missiles), it turns out, is different from what had been on offer to the Czechs and Poles, which was a system designed to intercept intercontinental ballistic missiles. The announced sale of one system, however, signalled the end of the other. On September 17th, the Obama administration confirmed it would abandon plans for an MDS based in Poland and the Czech Republic. In this Commentary, journalist and researcher Piotr Zalewski (Istanbul) assesses the implications of this move for Turkish-US relations and their neighbours and allies