Demonstration in Afrin (top) to support the YPG
and the YPJ
against the Turkish military operation, and demonstration in Bizaah
(bottom) to support the Turkish military operation in Afrin against the YPG and the YPJ, 19 January 2018.
After forces loyal to the Assad government pulled out of Afrin in 2012, Kurdish YPG forces took control of the territory. Afrin managed to maintain some trust with both the Syrian government and its neighboring rebel groups. In February 2016, during the latter part of the Battle of Aleppo, Syrian government forces cut off the rebel supply route to Aleppo. Subsequently, the SDF moved eastward out of Afrin, and successfully attacked the rebels, capturing the Menagh Military Airbase and the town of Tell Rifaat. In response, Turkish forces shelled SDF positions across the border to protect the rebel-held city of Azaz. In 2017, Russian military troops stationed themselves in Afrin as part of an agreement to protect the YPG from further Turkish attacks.
Turkey had been fighting PKK and other groups in southeastern and eastern Turkey for several decades. The Kurdish–Turkish conflict is estimated to have cost 40,000 lives. The Turkish government has publicly stated that it does not recognize a difference between the Syrian YPG forces and PKK, and says both are terrorist organizations. While the PKK has been designated as a Foreign Terrorist Organization by the United States, the United States' position on the YPG is that it is not a terrorist organization, a stance that has generated much conflict between the two NATO allies. Despite this, the CIA named the PYD as the "Syrian wing" of the PKK in its World Factbook on 23 January 2018. On 14 February, Director of National Intelligence described YPG as the Syrian wing of PKK in its new report.
During the early stages of the operation, United States Secretary of Defense James Mattis noted that Turkey was the only NATO ally with an "active insurgency" within its borders. Mattis acknowledged that Turkey has "legitimate security concerns" regarding PKK, and said Turkey had consulted the United States prior to launching the offensive. The offensive came amid growing tension between the Turkish and American governments over the latter's support of the Syrian Democratic Forces, which are made up primarily of Kurdish fighters of the YPG, which Turkey considers to be a branch of the PKK. In particular, Turkey objected to announced plans by the US to train and equip a 30,000 strong SDF border force, which Turkey claimed posed a direct threat to their security. "A country we call an ally is insisting on forming a terror army on our borders," Turkish President Recep Tayyip Erdoğan said in a speech in Ankara. "What can that terror army target but Turkey? Our mission is to strangle it before it's even born."
According to media reports with reference to sources in the Syrian Kurdish leadership, shortly before the Turkish incursion, as an alternative option, Russia proposed that the Kurdish authorities in Afrin recognise the Syrian government's control in the region; the proposal was rejected at the time.
The Afrin offensive has jeopardized the Astana Peace Process by placing the major parties—Russia, Iran, and Turkey—on opposing sides of the conflict. According to an Iranian official, Tehran has warned Ankara that "many parties might want to see Turkey stuck in a quagmire" and has advised that Turkey "try to contain this adventure". Tehran's position is that the Kurdish fighters are not acting independently, but rather are receiving support from multiple sides in the conflict.
In the days prior to the offensive, Turkey and the Turkish-backed Free Syrian Army exchanged artillery fire with YPG militants along the Turkish-Syrian border near Afrin. The YPG shelled the TFSA-held town of Azaz. The Turkish state-run Anadolu Agency reported that Russian military observers in the Afrin area began withdrawing on 19 January 2018 in anticipation of a Turkish offensive on YPG positions in Afrin.
On 12 February, Turkey's Interior Ministry added former PYD co-leader Salih Muslim Muhammad to its "wanted terrorists" list along with several new names and offered money for information on his whereabouts. On 25 February, Salih Muslim was detained in Prague at Turkey's request. Turkish officials said that Muslim will appear before a court in Prague. Turkish Deputy PM Bekir Bozdağ said that Turkey is requesting Muslim's extradition. However Czech court released Muslim. Turkish Deputy PM said this was "a move in support of terror".