the syrian border town of jarablus, where turkey has recently launched a military offensive,  is of critical importance for the future of turkey, syria and the middle east alike. it is the last major gate of access to the west for the islamic state of iraq and the levant (isil), which has carried out numerous attacks in turkey as well, including the most recent one in gaziantep. isil established a self-declared caliphate after capturing mosul in june 2014 and started expanding its territorial base afterwards. the group seized large swaths of syria and iraq. however, the us-led coalition succeeded in pushing them back. now jarablus is the last significant region connecting isil with the rest of the world. having recently lost the city of manbij, the group has deployed a considerable part of its forces to jarablus. many believe that purging jarablus of isil would cause the group to lose further ground, which would also put the world at ease.

avoiding encirclement of turkey

after a civil war broke out in syria, pkk's syrian branch, pyd declared the establishment of jazira, afrin and kobane cantons in january 2014.

although turkey repeatedly told pyd to avoid taking unilateral actions and that syria's future must be determined by the syrian people as a whole, these warnings fell on deaf ears. the us engaged pyd as a land force in its fight against isil. in june 2015, pyd unified the jazira and kobane cantons. having seized the territory between these two cantons mainly from isil, the group also changed the demographics there.  

in the event of a further integration of these two unified cantons with the afrin canton, an entity ruled by pkk's syrian branch, pyd will emerge in northern syria along the entire turkish border, standing between turkey and the middle east. for now, these two cantons are separated by the region between jarablus and azaz. some 40 km part of this region from azaz to çobanbey belongs to opposition while the rest from çobanbey to jarablus is held by isil. 

time and again turkey has warned that pyd shall not cross to the west bank of the river euphrates, which ankara considers a "red line", in an effort to prevent unification of these two pyd-controlled cantons. it is also known that the us pledged that pyd will not go to the west of the euphrates. however, pyd did cross to the west of the river, taking the town of manbij. it's just that instead of moving along the turkish border, they moved along the south of it. the us says pyd forces will not remain in manbij, but they are currently there.     

more space for opposition forces

the russia-backed regime in damascus has inflicted a heavy push back on other opposition forces in syria for the last one year. aleppo, in particular, comes under occasional siege lately, which puts the opposition in a difficult situation. there is also no connection between the opposition forces in azaz and the opposition forces in idlib as damascus closed the corridor between the two in january. syrian opposition is now participating in turkey's jarablus offensive as part of the free syrian army. if jarablus and its surrounding area can be purged of isil, that would allow more space for the syrian opposition.