Is Shooting Down a Hijacked Plane against the Faith?

Please forgive me if I posted this question in the inappropriate forum

Recently, I was watching a documentary concerning Post-9/11 America. They mentioned that, should terrorists again hijack a plane and attempt to crash it into civilian areas, the US Air Force would be mobilized to shoot the plane down. This would kill both the terrorists as well as the civilians on the plane, but many more civilian lives would be saved.

If I am not mistaken, I remember reading something in the Catechism saying that one should not murder or unjustly harm another even if the lives and safeties of others are at stake.

So, is shooting down a hijacked plane against the faith?

In the scenario described there are two effects produced by the action of shooting down a plane hijacked by terrorists: stopping the terrorists and the death innocent people. Such moral actions need to be evaluated under the Catholic understanding of the principle of double effect:
[list]*]- 1 - The action must be either morally good or neutral.
*]- 2 - The bad effect must not be the means by which the good effect is achieved.
*]- 3 - The intention must be the achieving of only the good effect, the bad effect can in no way be intended and must be avoided if possible.
*]- 4 - The good effect must be at least equivalent in proportion to the bad effect.[/list]

Let us now address them:

  1. the action of shooting down a plane intending to do harm is at the very least morally neutral. In war it is never questioned whether anti-aircraft weapons used against enemy fighter planes are moral.
  2. The effect of stopping the terrorists is not achieved by killing the people on the plane. The effect of stopping the terrorists is achieved by shooting down the plane which also has the effect of killing the passengers. In other words its not morally permissible to shoot the hostage to then be able to capture the villain. In this case that is not what is happening since the action is not directly aimed at the passengers
  3. If there is any other method of stopping the terrorists it must be used. At this time there may be no other option than to shoot down the plane.
  4. Stopping the terrorists from killing perhaps hundreds or thousands of people is indeed at least proportional to the unintended effect of the death of the passengers.

The scenario described is essentially the equivalent of removing the fallopian tube during an ectopic pregnancy. While the action will save the life of the mother, it will also indirectly cause the death of the embryo. This procedure is well accepted in the Catholic moral theology tradition. So, yes it would seem to be on solid Catholic moral theological ground to shoot down a hijacked plane that is reasonably known to be attempting to use it to kill others.

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