First I would like to express my deep sympathy for the familiy of our murdered colleague.
The discussion until now covered a lot of aspects. However, there is one generic question I would like to bring up - not expecting an answer!
As already mentioned it's the system which has to blamed not the individual (swiss cheese model!)
But wherever human beings are involved, they make mistakes. Whether they create the system or form part of it. A human not making mistakes is not a human.
Can it be that an idividual not acting negligent or on purpose making a mistake can be sentenced for that - I mean sentenced for being human? I know this is not only possible but happens in reality.
The reason for that is, from my point of view, that puplic needs one (a face, a name,..) found guilty. Its somehow political. Concerning this issue society hasen't changed very much since 2000 years (or even longer). It's a matter of fact and therefor I do not hope that any major changes will occur in the near and middle future.
And it will always be the individual from the front-line who will be victimised.
Every ATCO and pilot has to live with the knowledge of his own human deficiency. Coping with that requires a strong nature.
The only thing remaining is to wish all of us good luck for the future!
dg