President Obama's recent visit to the Japanese city of Hiroshima is an opportunity to reflect on the moral ramifications of one of the most horrific acts of war in history. Indeed, the President himself—rather than issue a cheap apology for the event—called for just such an exercise in critical thinking.

At the time, the logic behind the use of the atom bomb on Hiroshima—and, in short order, also on Nagasaki—was a simple and compelling one. Many argued the alternative was a grueling trench warfare with suicide Japanese solders—a battle for every hill, every yard, every city and village that would extend the war and result in the loss of as many as a million more lives. That argument resonated with a war-weary America at the time: a Gallop poll showed 85 percent supported the decision to use the atom bomb against Japan.

But can the bombing be morally justified? Especially in a Catholic moral framework?

The short answer: I don't see how it possibly can.