Eight months after the Cuban Missile Crisis when the United States and the Soviet Union stepped back from the precipice of a nuclear conflict, President John F. Kennedy, the nation’s first Catholic president, gave the commencement address at American University in Washington, D.C., in June 1963.
President Kennedy concluded that address by saying the United States would “do our part to build a world of peace,” and work “not toward a strategy of annihilation but toward a strategy of peace.”
More than six decades later, as the specter of nuclear weapons continues to hang over the world, Cardinal Robert W. McElroy, the Catholic archbishop of Washington, spoke at American University on Oct. 2, 2025 on “Catholic Teaching on War and Peace,” as part of the Thornton Lecture Series sponsored by the AUCatholic campus ministry program there.
Noting that the Catholic Church has consistently called for nuclear weapons to be eradicated from the world, Cardinal McElroy said Pope Francis built on the teachings of previous popes to spark “a new moment” in Catholic teaching on war and peace, placing nonviolence as the centerpiece of that teaching rather than the just war tradition, and also speaking out against the concept of nuclear deterrence and condemning the possession of nuclear weapons.
“Pope Francis viewed deterrence not as a source of peace, but a destabilizing element in the international system that creates a false sense of security, encourages the proliferation of nuclear weapons, threatens the environment and robs from the poor,” Cardinal McElroy said.
That pope said deterrence had not led to disarmament, but toward a buildup of nuclear weapons among more and more countries of the world.
“As a consequence, Pope Francis categorically condemned the possession of nuclear weapons as morally illicit, as do most countries of the world now. Discerning the implications of this dramatic shift in Catholic teaching constitutes a central task for all of us,” Cardinal McElroy said.
Washington’s archbishop underscored the need to move toward “collective action to eliminate the arsenals of the world so we can truly have nuclear disarmament. The events of the past year, which have witnessed an alarming confrontation between India and Pakistan and the bombing of the Iranian nuclear facilities in an attempt to prevent that nation from achieving nuclear weapons, make clear that our willingness to tolerate the nuclear status quo should end.”
Honoring a legacy at American University
The cardinal’s talk at American University’s School of International Service drew a standing room crowd. This fall marks the 60th anniversary of the Kay Spiritual Life Center, where services and activities for the AUCatholic campus ministry and other faith groups at the university are held.
The Thornton Lecture Series is named for Dr. Karin Thornton, who served the Catholic community at American University for almost 40 years, including as the longtime associate Catholic chaplain there, before her death in 2018.
“It is profoundly fitting that tonight’s topic, Catholic perspectives on war and peace, is the theme of the lecture in her name. Karin’s own life story makes this conversation deeply personal and eternally relevant,” said Christine Gettings, the director of International Programs and Partnerships in the university’s School of International Service.
Gettings noted that Thornton was born in Berlin in 1929, and “her early childhood was shattered by the ravages of World War II and fascism.” Her family found refuge in Switzerland, and she ultimately immigrated to the United States.
“Tragically, in our world today, her experience is mirrored by millions, as war and conflict have displaced more people than at any point of time in modern history,” Gettings said, adding, “She understood, firsthand, the acute need for welcome, community, and peace on a college campus for those whose lives had been upended. Having found that welcome herself, she dedicated her life to paying it forward at American University. Her service ensured that the Catholic community would always be a sanctuary for everyone, regardless of where they came from or what they had endured.”
Prophets of peace today
As he opened his talk, Cardinal McElroy noted he had participated in a Pilgrimage of Peace to Japan in August coinciding with the 80th anniversaries of the U.S. atomic bombings of Hiroshima and Nagasaki there. Cardinal McElroy said one of the most profound elements of that visit was the presence of the Hibakusha, the survivors of the atomic bombings in Japan.
“They are the great prophets of peace in a world which knows the madness of war all around us, and they speak of the most terrible realities of what war can bring, but also what hope can bring and working for peace can sustain. So it is in their witness that I stand with you tonight and talk about this present moment in Catholic teaching on war and peace,” the cardinal said.
A landmark encyclical
With his landmark 1963 encyclical Pacem in Terris (Latin for “Peace on Earth”), Pope Saint John XXIII “created a new moment in Catholic thought” in the wake of the horrors of World War II and the previous year’s Cuban Missile Crisis, the cardinal said.
Cardinal McElroy recalled how he was a young boy during that crisis, and students then had drills to get under their desks and shield their eyes in case of a nuclear attack. “We lived for 13 days with this,” he said of the Cuban Missile Crisis. Recalling those anxious days when the United States and the Soviet Union pulled back from the brink of nuclear conflict, he said, “It was a horrific moment of great peril.”
Pope John XXIII in his encyclical “placed the threat of nuclear weapons vividly in front of the world,” the cardinal said. “He fearlessly proclaimed that the issue of nuclear weapons was at its heart a moral question, not a political one, and that the world would have to forge a way forward toward nuclear disarmament if the future of humanity was to be assured.”
Washington’s archbishop said Catholic teaching today “is once again undergoing a new moment in its teaching on war and peace. This new moment, like the encyclical of John XXIII, is rooted in Catholic faith and tradition and unswervingly attentive to the signs of our own age, when nuclear proliferation is a growing danger that threatens to engulf us all.”
Three shifts in Catholic teaching
The cardinal said three key shifts in Catholic teaching on war and peace are taking place.
“First, the continuation of wars among nations and within societies, enlisting devastating weapons and resulting in countless deaths have pointed to the need to fundamentally renew and prioritize the claim of active nonviolence as the primary framework for Catholic teaching on war and peace,” Cardinal McElroy said.
The second shift in that Catholic teaching, he said, involves “the continuous misuse of the just war tradition and its susceptibility to functioning as a justification for rather than a restraint upon warfare, (which) challenges the Church to refine this ethical framework if it is to provide morally informed guidance in assessing those situations where nonviolence fails.”
The third shift, the cardinal said, involves Catholic teaching in response to “the failure of nuclear deterrence as a step on the way to disarmament (which) has produced a situation where we are facing the breakdown of the arms control regime and the possibility of the use of nuclear weapons.”
Cardinal McElroy said that in confronting these realities in its teaching on war and peace, “The Church must engage with the world in this new moment in order to contribute the deepest wisdom of Catholic faith and tradition in a perilous age. And Catholics in every land must grapple with these foundational questions if we are to be faithful to our lives as citizens and believers.”
Nonviolence as the centerpiece
The cardinal noted how since Pacem in Terris, every pope has spoken out strongly against war.
“But it was Pope Francis who died this past year who utilized the trajectory of all of these statements to construct a framework for Catholic teaching on war and peace that placed nonviolence rather than the just war tradition as the centerpiece of Catholic teaching on war and peace,” Cardinal McElroy said. “…Pope Francis shifts it and says for us who are followers of Jesus Christ, who is the one who rose to give us peace, the option is peace first. That must be the primary path and ethic on war and peace.”
Cardinal McElroy said a 2012 book by Erica Chenoweth and Maria Stephan, “Why Civil Resistance Works,” offered a quantitative study of wars and conflicts, and showed that “nonviolent resistance can often be significantly more effective than armed defense in achieving the sustainable vindication of human rights,” while also offering “possibilities for reconciliation that don’t exist in confrontations of a military nature.”
The cardinal noted Pope Leo has also emphasized nonviolence, saying, “From local and everyday situations to the international order… nonviolence, as a method and a style, must distinguish our decisions, our relationships and our actions.”
Limits of the just war criteria
The resonance of nonviolence in the gospel of Jesus and its effectiveness in the real world points to the need for the Church to re-evaluate its just war teaching, the cardinal said. The just war tradition, he said, has been a cornerstone of Catholic teaching on war and peace and of the moral tradition of most of the West and international society.
“Now in Catholic thinking, the just war tradition has always been meant as a containment to war, to limit war, not to give permission for war. But one of the problems is once policymakers begin to grapple with these thoughts, they find more and more reasons to make those conditions elastic, and thus they find it as a pathway leading to war, rather than as a constraint to war,” Cardinal McElroy said.
He noted how the just war criteria says that war is to be avoided, but it can be allowed in certain circumstances, including to defend a country when it has been attacked, such as the current situation of Ukraine defending itself after being invaded by Russia, or the case of the United States and a coalition of countries defending Kuwait after it had been invaded by Iraq in 1990.
The just war tradition, the cardinal noted, also requires that all other options have been tried to avert war, and that it’s a last resort, and it involves limitations on warfare, that civilians not be targeted, and that the military action in response be proportional.
Cardinal McElroy said that in modern times, policymakers seem to use the just war criteria as a checklist to validate going to war.
“As a real constraint on war, it fails in the modern age,” he said, pointing out the problem that “the just war criteria say nothing about how to end a war. One of the immense problems of wars is, they don’t end, they keep going. When we look around the world and see the wars going on these days in which we live, and see the human suffering coming from them, in a place like Ukraine, it’s a terrible situation. Palestine, Gaza, it’s horrific, this is terrible suffering that’s occurring.”
Concluding his talk, the cardinal said, “Today we must look at these questions of war and peace, and why the Catholic teaching has shifted this dramatically. Its heart is still in the same place, the same central declaration of ultimate opposition to war, but the constraints the Church puts on war are more dramatic now, because war has become so much more barbaric.”
Reflections from AUCatholic students and staff
Father Ivan Pertine, the chaplain for the AUCatholic campus ministry program who also serves as the general director of the Saint John Society of priests and missionaries, welcomed people at the talk. Allie Dunbaugh serves as the campus minister for AUCatholic, and also assisting the program are two men in formation to become priests of the Saint John Society and seven men and women who are voluntary missionaries there.
In interviews afterward, AUCatholic students and staff reflected on the cardinal’s talk and on the campus ministry program there.
Ella Bordwell, the president of AUCatholic who is junior from the Westchester area of New York, noted she is majoring in international service at American University and appreciated what the cardinal said about war and peace.
“My specialty is in human rights, ethics and justice, and I work in the anti-human trafficking field, and a lot of what we talk about is what is morally right, in war, in situations, in economics, in capitalist societies... My faith is what I use to ground me,” she said.
Bordwell said the AUCatholic campus ministry program and the community there are “a huge part of balance in my life, and of truth seeking and of friendship,” helping her deepen her love for Christ and her faith, and helping her grow in her faith and not stay stagnant.
Elinor Harrison, a sophomore from Chatham, Virginia, studying public health and anthropology at American University, said she appreciates how she was welcomed into the AUCatholic community as a freshman, and that inspired her to receive her First Communion and the sacrament of Confirmation at the Easter Vigil this past spring. Harrison said receiving those sacraments have helped her “feel at home with my faith. It just meant that I was going to be a changed person, which I had been seeking for a long time.”
Joey Oliva, a junior at American University from Philadelphia who is majoring in international relations and minoring in Italian language studies, said, “I had never heard before the perspective that Cardinal McElroy had presented about the just war not being applicable in today’s day and age. I always hear that it’s something that should be upheld and championed in the western world.”
The cardinal’s presentation on active nonviolence, he said, “really resonated with me… I think this is something Christ would preach today.”
Oliva, who serves as the vice president of hospitality at AUCatholic, said he appreciates the opportunities that the campus ministry program has given him to grow in his faith.
“Also, I’ve really enjoyed the community and the friendships I’ve made from it. I think those Christ-centered friendships are friendships that I will hold probably for the rest of my life, and I’m just so incredibly grateful for them,” he said.
Allie Dunbaugh, the program’s campus minister, praised the faith of the AUCatholic students, saying they “are so on fire for Jesus. They really have a deep love for Him and a passion for sharing Him. They really have missionary hearts.”
Regarding Cardinal McElroy’s talk on Catholic teaching on war and peace, Dunbaugh said she appreciated his message that “peace needs to be the primary aim, the primary goal of everyone… It should be something we’re striving for.”
(For information on AUCatholic, go to the campus ministry’s website at https://aucatholicdc.org/.)
