Wenn Putin is doing an Erdogan- angeblich attacking IS, actually hitting syrian/kurdish rebel groups- we in Europe can look forward to even more refugees. What some people need to understand is that the refugees are principally fleeing the syrian army and the more radical of the local rebel groups,IS having 'also ran' status in this respect.
A while back, a german journalist and former politician was able, with guaranteed safe passage, to look behing the IS scenery for a few weeks. According to him,IS is principally an Iraqi sunni organisation, called into life to fight the perceived discrimination of the iraqi sunnis by the shia majority.In his opinion, the only way to defeat IS is for the iraqi government to give the sunni minority full equality with the shias and so remove the need for sunnis to support IS.
Assad will have to go eventually, but as long as his army, and the PKK, are offering the only effective resistance to IS, the 'the west' will have to bite on the bullet and find a way to work with Assad and the Kurds.