Personally, I cannot see how a "well-trained" person could "accidently" discharge a firearm. Spontaneous combustion? It should never have been out of its case, holster or where-ever it is normally kept while in flight, unless it was thought to be used. He shouldn´t have been "checking it," loading it or showing it during routine flight. That seems simple enough...
Certainly I agree with you. What an embarrasment. I hope the retribution is swift and harsh. Can you imagine how the non-FFDO crewmember sitting next to him felt?
As to comparisons US vs. EU, oh now stop. If your ground screening, etc. were as pathetic as ours, you'd be begging for a pistol too....
Let me give you the bottom line: we've got all the guns in the world, and civil rights laws that will stop any confiscation. Given that set of initial conditions, can you really argue against the good guys arming themselves as well?