Because Merkel made a deal with him regarding the refugee crisis. Apparently Europe isn't in control of it's own external borders anymore (in case of Greece th

Because Merkel made a deal with him regarding the refugee crisis. Apparently Europe isn't in control of it's own external borders anymore (in case of Greece this is to be expected of course). And the Schengen treaty removed many internal borders. So now Merkel wants Erdogan to stop refugees on behalf of Europe. Erdogan gained a lot of indirect power in Europe with the agreement and (IMHO) this is not a good thing.