The Arab world and its neighbors are stuck in a violence trap. The fighting in Libya, Syria, Yemen and Iraq, together with the predations of groups like the Islamic State, is destroying the economic links needed to ensure long-term political stability. Indeed, by redrawing the region's economic boundaries, the latest wave of violence has brought about a veritable trade shock, the true scale and significance of which has largely gone unnoticed.

Even as the proliferation of armed groups makes borders more porous to conflict, it is hardening them against trade. The consequences are being felt most acutely in the Levant, where improved transport and trade reforms had strengthened economic ties between Iraq, Jordan, Lebanon and Syria.

Trade among these countries had been higher, on average, than among their Arab peers, but it has collapsed as violence has mounted. Syria's border closures, in particular, have impeded regional trade, by cutting off a key route connecting the wider Levant, the Gulf States and Turkey. The unnoticed casualties include Lebanon's apple growers, who survive on exports. Since 2011, Lebanon has lost almost all of its export markets in Jordan, Iraq and the Gulf.