Turkey is trying to use refugee flows into Europe as a lever to get European assistance for its war in Syria. From Tim Kirby at strategic-culture.org:
It now looks like Europe may be moving towards Migrant Crisis 2.0 as footage from the Greek border is pouring in over the Mainstream Media. However the key player to pay attention to is Turkey, they may have started the new migration problem and thus they may be the ones who can end it.
The original Migrant Crisis at the start of the Syrian Civil War in 2011 was portrayed as an organic consequence of events that happened on their own. The Mainstream Media pushed hard to sell the idea of the migrants as victims of either circumstance or Assad, who deserved to get everything they want from the wealthy West. However, this time around the narrative is surprisingly different (at least for the moment) as Migrant Crisis 2.0 is not really getting much media push, in fact the opposite appears to be happening, possibly due to the fact that Erdogan made it so bluntly clear that with his decision to allow migrants to leave Turkey is directly connected to his failures in Syria. If he doesn’t get a piece of Syria, then Europe will.