IT WAS meant to be a game-changer. When a deal between the European Union and Turkey was struck in March with the aim of limiting the numbers of asylum-seekers coming to Europe, many in Brussels felt cautiously optimistic. Angela Merkel, the German chancellor, claimed it offered a “sustainable, pan-European solution”. In exchange for visa-free travel for some of its citizens, €6 billion ($7 billion) in refugee aid and revived talks on possible future accession to the EU, Turkey was to take back migrants who had made their way to Greece and try to secure its borders. Faced with perhaps another million refugees making their way to Europe this year, it appeared to be the only way to bring some order to the chaos. The number of refugees coming to Europe has indeed dropped (see chart). Yet the agreement is looking more and more murky. It risks undermining both the reputation of the EU and its relationship with Turkey, from whose shores hundreds of thousands of refugees set off last year on their journey to Europe. ...