I think it were back in 2008 that the potential Terrorist miss-use of GPS via drone bombs were first mooted here on pprune. There were much derision of the possibility at the time.
It is now proven that the terrorists have GPS guided drone bombs and that there is no easy way as of yet to stop an inflight terrorist drone attack. The GPS signal either needs to be jammed or shut off. The Israeli's have proven the huge, and unsustainable, cost of defeating individual GPS guided terrorist drone attacks.
Until the GPS guided terrorist drone threat can be neutralised, any pilot/ATC reliance on ADS-B is a disaster waiting to happen.
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