The Reason Behind It
Think what you like about the prospect behind this concept coming to fruition, however it's premised upon a very forceful motivator. Since 9/11 there have been numerous EU instances of airliners and bizjets out of contact for protracted periods and suicidal light aircraft impacting upon the lawns of the German Chancellery etc. In all instances as the aircraft moved through Europe, crossing individual EU states without anybody being able or willing to produce a shootdown decision, the potential for an ultimate fiasco was obvious.
.
Not only do 40% of EU states lack an intercept capability, the incentive is always there just to see the rogue aircraft to the next border and then breathe a sigh of relief as it becomes yet another reluctant pollie's responsibility. NATO has no remit to intercept or shootdown rogue/hijacked aircraft, so the problem can't be fobbed off on it.
.
This project is seen as the last best hope for taking this career-ending nightmare potentiality away from being a politician's burden. In the event a martyr aircraft did get through, the politicians can always say that the system was in place to ensure that the suicide mission failed and that they therefore cannot accept any responsibility. So you could say that the project has the fervent hopes (and economic strength) of the EU behind it. Even if it doesn't come to fruition for some years, the EU national leaders can point to the project and say, after a successful attack, that they were developing a coping mechanism and not allowing the grass to grow under their feet.
.