Ok - let me be provocative.
Lets tighten up security by fitting prop locks and identity cards to gain airside access. The worst happens. What do we do now?
If we hadnt bothered we would say ah, we are going to fit prop locks and enhance airside security, everyone would be happy.
Of course it is doubtful the prop locks or enhanced security had any effect at all other than
PR, but the politicians are happy we have done something in the second case. In the first case they will argue all that can be done was done so the only remaining option is to ban it altogether or insist on something totally draconian.
Are aircraft such a good way of getting in and out?
Personally I would opt for a yacht. The movement in yachts across the channel is significant - there is no paperwork trail, no FPLs and many more places to put people ashore.