Until a few weeks ago, analysts and observers of Turkish-American relations projected that the most significant issues in bilateral relations for the year 2019 would be the S-400 and the divergence of interests and strategies in Syria. Most of these observers asserted that these two issues will be the primary source of tension between the two countries. Given the difficulty to tackle these issues, many even provided a bleak assessment of the future of the bilateral relations. In the last two weeks, however, there have been some significant developments. First of all, two weeks ago, the U.S. State Department informed the U.S. Congress about a proposal to sell Patriot missiles to Turkey. Although the Patriot missile defense systems issue was discussed earlier, the announcement came in a critical period for Turkey-U.S. relations, when the S-400 missile defense systems deal is being perceived as a looming crisis; mostly due to the discussions about the adoption of Countering America's Adversaries Through Sanctions Act (CAATSA) and the report from the U.S. Defense Department following the National Defense Authorization Act (NDAA). The decision to sell Patriot missiles to Turkey was a welcome development for relations. However, there are so many unanswered questions about the potential impact of such a deal. First of all, in regards to the Patriot missiles, the negotiations about the details will take place in the coming weeks. These negotiations will determine the conditions of the Patriot missile sales to Turkey. If there will be a condition in the sale of the missiles related to Turkey's purchase of S-400s, we can one more time find relations turn to major tension. In regards to S-400s, any decision to delay the transfer of F-35 Lightning II fighter jets or an attempt to push Turkey out of this project would again constitute a major crisis. Thus, although there is a new opening in bilateral relations, the cooperation between the two countries in the defense industry necessitates more sensitivity to Turkey's national security requirements. In multiple different instances, the difficulties that Turkey faced in purchasing the weapon systems from the U.S. negatively affected the mutual trust between the two. In fact, it was one of the reasons why Turkey tried to find alternative sellers in order to meet its security needs. A second development took place following President Recep Tayyip Erdoğan's phone call with U.S. President Donald Trump. The U.S. administration officially announced its decision to withdraw troops from Syria. This decision was taken while Turkey was preparing its next cross-border operation to clear the border area from terrorist groups. This decision also provides an important opening in another potential crisis between the two countries. The disagreement between the two in regards to the Syrian crisis was one of the key elements negatively affecting bilateral relations over the past five years. With the withdrawal decision, a new period may start; however, again, just like the Patriot decision, the details of this withdrawal will determine the future of Turkish-American relations. If steps to the withdrawal take place in close coordination with Turkey, it can pave the way for consolidating cooperation in the region. This could increase the coordination between the two parties not only to deal with the threats to the regional security but also to find the diplomatic and political solutions to the problems in the region. Again, just like the S-400 issue, Turkey's national security concerns should be taken into consideration by the U.S. administration in this process. For instance, the People's Protection Units (YPG) will continue to be a major threat to Turkey and regional stability. Turkey will play a critical role in the stabilization of the area east of the Euphrates and in the enduring defeat of Daesh; however, it will not cease its counterterrorism operations when its national security is threatened. Indeed, for Turkish-American relations, 2019 provides an important opportunity. The two states can reach an agreement on the two most challenging issues in their relations, namely S-400s and the Syria crisis. However, the effective use of this opportunity depends on close communication and coordination in both capitals and quick containment of the potential crises in bilateral relations. This article was first published by Daily Sabah on December 28, 2018.