Just War and the Bombing of Hiroshima and Nagasaki

DIFFICULT MORAL QUESTIONS: What is Catholic just war theory, and how does it apply to ISIS and Syria, and to the bombing of Hiroshima and Nagasaki in 1945?

Nagasaki, the heart of Catholicism in Japan, lies in ruins following the bombing of the city on Aug. 9, 1945. The remnants of the Catholic cathedral can be seen near the hills on the left side of the picture.
Nagasaki, the heart of Catholicism in Japan, lies in ruins following the bombing of the city on Aug. 9, 1945. The remnants of the Catholic cathedral can be seen near the hills on the left side of the picture. (photo: U.S. National Archives and Records Administration)

Q. My name is Russell and I'm emailing from New York state. Could you explain Catholic just war theory to the readers and how it applies in regards to the dropping of the atomic bombs on Hiroshima and Nagasaki in 1945, as well as the current state of affairs against ISIS and Syria?

A. In the run up to the 2003 Iraq War, the president of the United States Catholic Conference of Bishops published the following statement:

“With the Holy See and many religious leaders throughout the world, we believe that resort to war would not meet the strict conditions in Catholic teaching for the use of military force.”

The “strict conditions” he refers to are the traditional just war criteria, which come down to us in various forms, one of which is found in the Catechism of the Catholic Church. These conditions are best understood as moral principles (or norms of justice) guiding those who engage in war to deliberate, judge and choose rightly.

Traditionally, there are two sets of principles, one governing the choices of those who are contemplating going to war, referred to as jus ad bellum. And a second set governing the activities of those who are engaged in prosecuting a war, referred to as jus in bello.


Jus Ad Bellum

The Catechism’s list of jus ad bellum norms include:

  1. Just cause: “The damage inflicted by the aggressor on the nation or community of nations must be lasting, grave, and certain.”
  2. Last resort: “All other means of putting an end to it must have been shown to be impractical or ineffective.”
  3. Probability of success: “There must be serious prospect of success.”
  4. Proportionality: “The use of arms must not produce evils and disorders graver than the evil to be eliminated.”
  5. Legitimate authority: “The evaluation of these conditions for moral legitimacy belongs to the prudential judgment of those who have responsibility for the common good” (2309).

For a decision to go to war to be just, all five conditions must be met. If any one condition is violated, going to war is unjust. And if the choice to conduct a war is unjust, then no means chosen in the prosecution of that war can be justly chosen. (Medics and chaplains do not engage in acts of war.)


Jus In Bello

The Catechism itemizes two jus in bello norms:

  1. Upright Intention: “Non-combatants, wounded soldiers, and prisoners must be respected and treated humanely” (2313). This is sometimes referred to as the principle of non-combatant immunity. Most fundamentally, it prohibits the intentional killing of civillians and other non-combatants.
  2. Proportionality or Discrimination: This prescribes that the measures of force adopted in the prosecution of a war should not be in excess of what is necessary to achieve the military advantage anticipated by one’s precise (and presumptively legitimate) military objective. Therefore, acts of war that cause “indiscriminate destruction” are gravely immoral (2314).


Hiroshima and Nagasaki

You ask about the dropping of the atomic bombs on Hiroshima and Nagasaki in August 1945. Since these were acts of those engaged in prosecuting the Second World War, firstly, but not only, of the U.S. Commander in Chief (President Harry Truman), we assess them in the light of the jus in bello principles.

Both Hiroshima and Nagasaki were essentially civilian cities, not large military compounds or combatant training camps. In fact, Nagasaki was the cradle and epicenter of Japanese Catholicism. The two atomic bombs, Little Boy and Fat Man, were, to use a contemporary idiom, weapons of mass destruction. That is, each was chosen precisely for its capacity to cause massive and indiscriminate harm. Tens of thousands of civilians were killed by each, and the property at and around the respective ground zeros was reduced irreparably to rubble and ash.

We may confidently conclude without equivocation or doubt that the dropping of these bombs over Hiroshima and Nagasaki violated both the conditions of upright intention and proportionality. They rank among the great moral atrocities committed in military history.

Although neither the Second Vatican Council, nor any subsequent Church document, has ever condemned by name the bombings of Hiroshima and Nagasaki, the Council clearly meant for these acts to be subsumed under its condemnation of “total war” in Gaudium et Spes:

“Any act of war which aims indiscriminately at the destruction (destructionem indiscriminatim tendit) of entire cities, or of extensive areas along with their inhabitants is a crime against God (crimen contra Deum) and man himself. It merits unequivocal and unhesitating condemnation” (80; see also Catechism, 2314).


ISIS and Syria

You also ask about the armed conflicts against ISIS and in Syria. An assessment of these is more complex because neither conflict can be considered a U.S. war in any straightforward sense. Perhaps another DMQ column might be dedicated to these issues alone. But here are a few initial thoughts.

First, it must be kept in mind that the jus ad bellum norms do not become irrelevant once a conflict begins. One’s assessment of the choice to go to war needs to be constantly reassessed in the light of new information that arises in the course of the war’s prosecution. A war judged to be just at the beginning may be unjust to continue if the reasons originally thought to justify it prove to be false or if other conditions relevant to the war’s justification change.

Second, the immediate duty to assess any armed conflict lies with those who are competent to make executive military decisions. These authorities are often privy to classified information unavailable to others. A conflict that does not appear to Joe Citizen as meeting the conditions for, say, just cause or last resort, may look very different when assessed in the light of classified data.

Third, since as I have suggested neither our strategizing against ISIS nor our aiding of Syrian rebels constitutes a decision to wage or prosecute a war in any classical sense, the application of the two sets of moral principles needs very careful consideration.

For example, who has the rightful power — legitimate authority — to authorize military intervention against ISIS? Or to aid rebels in their war against an authority that the U.S. once supported as rightful? Or on what basis does the U.S. threaten action against third parties who provide aid to the Assad government similar to the way it (the U.S.) provides aid to the rebels?

Having said all this, it seems to me that if our country is invited by legitimate foreign authorities — and assessing legitimacy can be complex — to intervene in a foreign conflict, U.S. authorities have the duty independently to assess the justice of intervention in the light of the ad bellum and in bello principles. And that assessment can only rightly be rendered in the light of the knowledge that the U.S. government’s principal duty is to protect and promote the common good of the United States.

The president should ask whether the duties imposed on him in virtue of his oath to defend the Constitution and protect the domestic tranquility require him to this sacrifice of U.S. lives, expenditure of U.S. fortune and toleration of lasting long-term harm to genuine U.S. interests (e.g., intractable Middle Eastern hostility toward the U.S.). If the answer is No, there should be a strong presumption against intervening in foreign conflicts.

This is not isolationism or narrow nationalism. It follows from a proper understanding of the nature of civil authority. For if some public authority deliberately makes a decision of this magnitude believing it is manifestly contrary to the common good of the community it is charged with protecting and promoting, then it must have very grave reasons for doing so.

Our almost addictive penchant for military intervention whenever it serves a very narrow conception of national self-interest, and worse, of picking winners and losers in foreign conflicts without serious assessment of the justice of the related cause, is very problematic.