The Catechism does say this: “…teaching of the Church has acknowledged as well-founded the right and duty of legitimate public authority to punish malefactors by means of penalties commensurate with the gravity of the crime, not excluding, in cases of extreme gravity, the death penalty….If bloodless means are sufficient to defend human lives against an aggressor and to protect public order and the safety of persons, public authority should limit itself to such means,…”

In this case, terrorism, it is certainly of extreme gravity. Thus the Church teaches that the death penalty is permissible.

And, in regard to protection of public order and the safety of persons, serious consideration must be given (1) to the real risk (for which there are ample precedents) that other terrorist allies/comrades of imprisoned offender(s) will take or threaten the lives of innocent others so as to force the release of the imprisoned, and (2) to the lack of firm deterrent that western world imprisonment presents.

It is certainly legitimate to judge that, in this case, Church teaching allows the application of the death penalty, and that the death penalty might be appropriate.

In the circumstances, this is not an occasion when bishops should enter the public arena in an attempt to pre-empt what might be a perfectly legitimate imposition of the death penalty.