Is the use of biological warfare or chemical warfare a mortal sin


I know about the Just War teaching of the Church but what tactics of war would be unjust?

Would using biological or chemical weapons be unjust (e.g. World War I use of gas)


I believe that they’re considered so, yes, particularly because of the unnecessary suffering that they cause.


2313 Non-combatants, wounded soldiers, and prisoners must be respected and treated humanely.

Actions deliberately contrary to the law of nations and to its universal principles are crimes, as are the orders that command such actions. Blind obedience does not suffice to excuse those who carry them out. Thus the extermination of a people, nation, or ethnic minority must be condemned as a mortal sin. One is morally bound to resist orders that command genocide.

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."110 A danger of modern warfare is that it provides the opportunity to those who possess modern scientific weapons especially atomic, biological, or chemical weapons - to commit such crimes.

Canon Law says participation in genocide is a mortal sin. Nothing about grave matter regarding weapons but it’s still strong language condemning use of such weapons anyway.


In accordance with Romans 13, treaties must be obeyed. Furthermore, weapons must be able to be controlled, so such things as contagious biological weapons are forbidden. The target must be a legitimate military target.


yes, to create suffering is bad


YES!!!I do indeed believe it is!!


I am not sure. If they are used against a city, yes, it would be gravely unjust since it would involve indiscriminate killing of innocent people. But suppose they are used to target one specific individual. Say for example, used against Osama Bin Laden specifically and care was taken not to hurt anyone else. Why would this be different from using a drone, operated by someone 10,000 miles away to target him and assassinate him? Was the assassination of Osama Bin Laden justified? If so, would it make any difference if he had been targeted by someone close to him, using a chemical or biological weapon, or by an American 10,000 miles away operating a drone while sitting in front of a computer screen? Of course, pacifists will say that it is wrong to murder someone who you disagree with politically even though he may have been thought to have caused great harm to others.


There’s a difference between terrorists, who are non-state actors and therefore arguably hostis humani generis, and an enemy army, with whom treaties apply.


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