The Catechism of the Catholic Church (CCC) provides clear guidance on the moral evaluation of acts of war, particularly those involving indiscriminate destruction. According to CCC 2314, "Every act of war directed to the indiscriminate destruction of whole cities or vast areas with their inhabitants is a crime against God and man, which merits firm and unequivocal condemnation."12

The Catechism recognizes that the development of modern scientific weapons, especially atomic, biological, or chemical weapons, has increased the danger of such indiscriminate destruction in warfare.12 The use of these weapons, which cannot distinguish between combatants and civilians, is condemned as a grave moral evil that offends both God and humanity.

In summary, the Catholic Church firmly and unequivocally condemns any acts of war that involve the indiscriminate destruction of entire cities or large populated areas. This teaching is based on the moral principle that the targeting of innocent civilians is a grave violation of the dignity of human life and cannot be justified, even in the context of armed conflict.