Sorry, but what you and the article are suggesting, is basically shutting down aviation for the possibility that someone can/could get to someone else.
Of course they can but that also means we had better shut down all jury trials because someone maybe be able to influence one of the jurors.
There is no defense against a person willing to give up his own life for his political beliefs. Our present society and we as human beings are not geared for this scenario. This is not to say that we shouldn't do anything to protect ourselves but the pendulum has swung to far in the interests of security.
The terrorists have won beyond their wildest dreams and we did, and are doing, the job for them...