VATICAN CITY — The Catholic Church should focus on promoting active nonviolence, rather than refining just war theory as conflicts continue to flare up around the world and threaten peace, U.S. Cardinal Robert McElroy of San Diego said.

“In the life of the church, just war theories are a secondary element in Catholic teaching; the first is that we should not engage in warfare at all,” he said in an interview with Vatican News published Sept. 23.

The cardinal, an adviser to the Catholic Institute for Nonviolence, which is scheduled to open in Rome Sept. 29, said that the use of just war theory as a justification for war “is a major problem.” The institute will be inaugurated by Pax Christi International, a global Catholic peace movement.

The cardinal’s comments echo a sentiment repeatedly expressed by Pope Francis. In a 2022 interview with Telam, Argentina’s public news agency, Pope Francis stated it is “time to rethink the concept of a ‘just war.’“ Although he affirmed the right to self-defense, he said society must rethink how it uses the concept of just war, adding that “resolving conflicts through war is saying no to verbal reasoning, to being constructive.”

According to the Vatican, during a video call with Russian Orthodox Patriarch Kirill of Moscow that same year, the pope said, “There was a time, even in our churches, when people spoke of a holy war or a just war. Today we cannot speak in this manner. A Christian awareness of the importance of peace has developed.”

And in a 2023 message to the U.N. Security Council, he said it is time to decisively state that “wars are not just.”

Cardinal McElroy told Vatican News that all forms of violence “are contrary to the way of the Gospel at their core,” and that as conflicts increasingly emerge worldwide “it’s ever more important that the church be a witness to finding alternative ways to resolve these conflicts as they break out.”

“But the building of peace is a much broader endeavor than ending conflicts,” he added, noting that peacebuilding includes caring for people’s dignity and promoting solidarity, both of which are predicated on the absence of war.

Recalling Pope Francis’ 2020 encyclical “Fratelli Tutti, on Fraternity and Social Friendship,” the cardinal said the pope “is saying to us that we have to think in new terms.”

“We have blinders in our minds about the peripheries, and we think some regions are less important,” he said. “That is a poison and certainly contrary to the Gospel.”