Germanwings Crash 'Deliberate': Murder by Co-Pilot?

It's a revelation that will change the world of aviation. French prosecutors have said that the co-pilot of the Germanwings A-320 which crashed on Tuesday deliberately brought down the plane over the French Alps. The pilot of the aircraft, who was out of the cockpit at the time of the incident, was deliberately locked out of the cockpit and could not re-enter. Why would anyone do this? Was the co-pilot a deeply disturbed person, and what does this mean for civil aviation? We debate. (Video Courtesy: France 24)