"I don't know how many more people need to die at sea before something gets done," said Malta's prime minister, Joseph Muscat. "As things stand we are building a cemetery within our Mediterranean Sea."

He was talking about the part of the Mediterranean between the North African coast and the two islands that are the closest bits of the European Union: the Italian island of Lampedusa and his own country, Malta. In the past two weeks, almost as many migrants have died in that narrow stretch of water — only 120 km separate Tunisia's coast from Lampedusa — as died along the U.S.-Mexico border in 2012.

On the southern U.S. border they mostly die of thirst in the desert; in the Mediterranean they drown. The migrants pay the smugglers in Libya or Tunisia thousands of dollars each to make the crossing in small, unseaworthy, grossly overcrowded boats, but the smugglers don't go with them. They don't want to get arrested at the end of the journey. They just hand over the keys to the migrants.