lol the new chief sounds like a complete idiot. GCHQ is a relic from the cold war that should have been shut down years ago, all this 'terrorism' scaremongering isn't going to fool anybody.
Terrorism is not something from the cold war (there were very few terrorist attacks during the cold war), it is very much something from the 21st century.
I think the best way to avoid terrorist attacks is to allow for law enforcement agencies to better communicate with eachother and to allow for better policies to protect places that would likely be of interest to terrorists.
On 9/11 the terrorists did not breach any level of airport security as they used items that were legal to bring onto airplanes to hijack the airplanes