The disputes between Turkey and Syria are rooted in the ethnic approaches dating back to the Ottoman period, the divisive policies of the West, and the aftermath of the First World War. “Hatay” was declared an autonomous region under a 1921 treaty between Turkey and France. The situation remained unchanged until 1923. In 1923, this sanjak was attached to the Aleppo province, and later in 1925, it was directly attached to the region under the French mandate. In 1936, Syria and Lebanon became independent from the French mandate. The border between Turkey and Syria was demarcated according to the Aleppo protocols of 1930. Ataturk demanded that Hatay be annexed to Turkey. On January 27, 1937, the League of Nations adopted a resolution in Geneva that granted autonomy to Hatay. France and Turkey signed a joint statement on May 29, 1937, committing themselves to cooperate on independence of the province.
On the verge of the Second World War on September 2, 1938, the League of Nations gave ‘Hatay’ the status of a state. Two representatives in the Turkish Parliament were elected as the president and the prime minister of Hatay. After one year, they turned Hatay into a province of Turkey following a referendum on June 29, 1939. Then Syrian President Hashim al-Atassi resigned in protest at French intervention in Syrian affairs, disputed the referendum results, and denounced it as a violation of the 1936 treaty between France and Syria. These developments steered Syria towards nationalism and the Eastern Bloc, as the process of separation of the two neighboring countries became deep-seated.
After the Second World War, disputes over the Tigris and Euphrates rivers added to the problems plaguing their bilateral relations. Turkey’s Western-oriented policy on Palestine and the Arab wars deepened the rift between the two countries. Turkey’s move to join NATO brought Syria, a strategic territory in the Eastern Mediterranean, closer to the Soviet Union. After the spread of communism in the 1960s, the US forced Turkey to exercise political opening policy. One of the impacts of such policy during the 1960s and 1970s was the rise of the Kurdistan Workers' Party. The deep-rooted Kurdish ethnic bonds along the border areas between Turkey and Syria set the stage for differences between the two countries in the 1970s. A number of the Syrian opposition forces fled to Turkey amid the conflicts in Syria’s Homs and Hama in 1982. Therefore, the challenges to relations between Syria and Turkey escalated in the 1980s over various issues, including Hatay, the legal regime of the Tigris and Euphrates rivers, the PKK activities, Islamism, and the Cold War disputes.
After dissolution of the Soviet Union and the end of the Cold War, Islamists rose to power in Turkey and its Army enhanced its activities. In 1995 and 1996, tensions increased between Turkey and Syria. In 1998, Turkey stationed military forces along parts of the Syrian border, and threatened to take military action. The foreign ministers of Iran and Egypt mediated and contributed to negotiations between representatives of Syria and Turkey on October 19-20, 1998, in the Turkish port city of Adana, which resulted in the “Adana Security Agreement” on October 20 of the same year. The agreement includes the main text and four annexes. The main purpose of the agreement is removal of the obstacles to normalization of ties, while the subject of negotiations was “discussion on cooperation in the fight against terrorism.” According to the agreement, Syria approved the requests from Turkey and agreed to expel Ocalan, not to allow Ocalan and other PKK members to re-enter Syria, not to allow the PKK to establish camps, and to arrest the PKK members inside Syria. One of the articles of the agreement says, “Syria, on the basis of the principle of reciprocity, will not permit any activity which emanates from its territory aimed at jeopardizing the security and stability of Turkey. Syria will not allow the supply of weapons, logistic material, financial support to and propaganda activities of the PKK on its territory.” Moreover, the agreement stipulates that “Syria has recognized that the PKK is a terrorist organization.” The Adana Security Agreement also says, “Both sides have agreed to establish certain mechanisms for the effective and transparent implementation of the measures mentioned above.” The Annex 3 states, “As of now, the two sides agree that their border disputes are ended, and that none of them has any claims or rights accrued in the territory of the other side.” Furthermore, the Annex 4 stipulates, “The Syrian side understands that its failure to take the necessary measures and security duties, stated in this agreement, gives Turkey the right to take all necessary security measures within 5 km deep into Syrian territory.”
By signing this agreement, then Syrian president Hafez al-Assad indicated that he would not see the continuation of past disputes with the neighbor to be in Syria’s interests. The results of such approach, the election of Bashar al-Assad as Syrian president in 2000 and Recep Tayyip Erdogan as Turkish Prime Minister in 2002, an upheaval in Turkey’s foreign policy, and the US attacks on Afghanistan and Iraq helped improve the relations between the two countries.
After pulling its forces out of Iraq, the US has been trying since 2007 to bring Turkey and Syria closer together. The relations between the two countries improved rapidly as of 2008. Following the political and social developments in North Africa and West Asia, Turkey’s unexpected support for the Syrian opposition in 2011 spoiled the friendship. The Syrian government said Turkey had violated the Adana Agreement by arming the rebel groups inside Syria. Afterwards in 2012, the Turkish government claimed for the first time after 14 years that the Syrian government had provided direct support for the PKK. In a meeting with Erdogan in Moscow in February 2019, Russian president Vladimir Putin referred to the Annex 4 of the Adana Agreement and proposed implementing the agreement as a substitute for a US-Turkish plan for creating a safe zone in northeastern Syria. The Syrian government announced later that it was not committed to the agreement, but would be ready to resume honoring the agreement if Turkey stopped supporting the Free Syrian Army and the other armed rebel groups and withdrew its forces from the occupied regions of northern Syria. Amid the Idlib developments, president of Turkey cited the Adana Agreement as a reason for the legitimacy of deployment of Turkish military forces to Syria, giving rise to legal discussions about the document.
(The opinions expressed are those of the authors and do not purport to reflect the opinions or views of the IPIS)