The battle on the ground is finally slowing as Assad consolidates his grip, and separately ISIS's caliphate is being scotched from the landscape. But what the regional crisis reveals -- shrouded in the multi-layered surrogacy of this war -- is an ugly, ethno-sectarian disease spreading its infection way beyond Syria's borders. While we have all been distracted by the destruction and death inside Syria, it's what's happening outside that could become a serious cause for concern, too.

A proxy war without rival in recent time (CNN)