Merely an attack on a German steel producer — or is it a message to Germany?

This link will take you to an account of a sophisticated, network-enabled attack on a German steel producer that disrupted production and caused physical damage to a blast furnace.  We are the beginning, not the end, of an era in which proliferating and uncontrollable expertise, backed by very little capital, can be leveraged to cause huge damage to critical systems that reside on the same vulnerable infrastructure that supports middle school chit chat.