The United States Conference of Catholic Bishops on April 15 issued a clarification of Catholic teaching on war and the pope’s authority after Vice President JD Vance suggested Pope Leo XIV should be “careful” when speaking about theological matters, including the Church’s just war theory.
Vance cites just war tradition
Vance, responding to recent remarks by the Pope that God “is never on the side of those who wield the sword,” said there is “more than a thousand-year tradition of just war theory” within Catholicism. He added that, just as he must be cautious in addressing public policy, “it’s very, very important for the Pope to be careful when he talks about matters of theology.”
“If you’re going to opine on matters of theology, you’ve got to be careful, you’ve got to make sure it’s anchored in the truth,” Vance said, adding that he expects that standard from clergy.
🚨 JD VANCE RESPONDS TO POPE LEO:
— Eric Daugherty (@EricLDaugh) April 14, 2026
"When the Pope says that God is never on the side of those who wield the sword — there is more than a THOUSAND year tradition of Just war Theory."
"In the same way that it's important for the vice president of the United States to be careful… pic.twitter.com/fV0CkX93Ga
Modern applications of just war
While the Church’s just war teaching remains unchanged in the Catechism, modern popes and Church documents have increasingly questioned the possibility of its strict conditions being met in contemporary warfare.
Gaudium et Spes was the first magisterial document to state that modern weapons make the traditional criteria dramatically harder to satisfy, building on Pacem in Terris, which said “in this age which boasts of its atomic power,” war is no longer a “fit instrument” to repair violations.
More recently, Pope Francis’ Fratelli Tutti said it is “very difficult nowadays” to apply earlier just war criteria to modern conflicts, or “to speak of the possibility of a ‘just war.’ Never again war!”
Bishops issue clarification
In a statement, Bishop James Massa, chairman of the bishops’ Committee on Doctrine, said Pope Leo’s remarks fall within the Church’s longstanding tradition.
“For over a thousand years, the Catholic Church has taught just war theory, and it is that long tradition the Holy Father carefully references in his comments on war,” Bishop Massa wrote.
Citing the Catechism, he noted that a central condition of that teaching is that war can be justified only in self-defense and “once all peace efforts have failed.”
Bishop Massa also pushed back on the suggestion that the Pope was offering a personal theological opinion.
“When Pope Leo XIV speaks as supreme pastor of the universal Church, he is not merely offering opinions on theology,” the bishop stated. “He is preaching the Gospel and exercising his ministry as the Vicar of Christ.”
He said the Church’s teaching remains consistent in urging both moral restraint and a commitment to peace.
The bishop remarked, “The consistent teaching of the Church is insistent that all people of good will must pray and work toward lasting peace while avoiding the evils and injustices that accompany all wars.”.
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