“War is back in vogue, and a zeal for war is spreading,” Pope Leo XIV said in a forceful address on Jan. 9 to ambassadors from the 184 countries that have full diplomatic relations with the Holy See. “The principle established after the Second World War, which prohibited nations from using force to violate the borders of others, has been completely undermined.” 

“Peace is no longer sought as a gift and a desirable good in itself,” he said, “Instead, peace is sought through weapons as a condition for asserting one’s own dominion. This gravely threatens the rule of law, which is the foundation of all peaceful civil coexistence.”

The annual address to the diplomatic corps is considered the pope’s most important of the year in terms of world politics. The United States was represented by its ambassador Brian Burch. 

Leo’s words took on particular significance as they came from the first American-born pope, less than a week after the United States, at President Trump’s instruction, used force “to violate the borders” of Venezuela, in disregard of international law. 

Leo lamented that multilateralism and dialogue are “being replaced by a diplomacy based on force, by either individuals or groups of allies,” he stated in the traditional New Year’s greeting delivered for the first time in English.

In his talk, the first Augustinian pope drew heavily on St. Augustine’s The City of God, which he said “interprets events and history according to the model of two cities,” the city of God and the earthly city.

In it, he said, Augustine “warns of the grave dangers to political life arising from false representations of history, excessive nationalism and the distortion of the ideal of the political leader.”

He recalled that St. Augustine wrote:

There is no one who does not wish to have peace. For even those who make war desire nothing but victory; they desire, that is to say, to attain to peace with glory. For what else is victory than the conquest of those who resist us? And when this is done there is peace…. For even those who intentionally interrupt the peace in which they are living have no hatred of peace, but only wish it changed into a peace that suits them better. They do not, therefore, wish to have no peace, but only the peace that they desire.

“It was precisely this attitude that led humanity into the tragedy of the Second World War,” Pope Leo observed. 

The broken world order

He recalled that it was “from those ashes” of World War II that the United Nations was born in 1945, “as the center of multilateral cooperation, in order to prevent future global catastrophes, for safeguarding peace, defending fundamental human rights and promoting sustainable development.”

Recalling the role of the United Nations in mediating conflicts and protecting human rights, the pope said that “in a world facing complex challenges such as geopolitical tensions, inequalities and climate crises, the U.N. should play a key role in fostering dialogue and humanitarian support, helping to build a more just future.”

He emphasized the need for a reform of the United Nations to ensure that it “not only reflects the situation of today’s world rather than that of the post-war period, but that it is also more focused and efficient in pursuing policies aimed at the unity of the human family instead of ideologies.”

In this context, he drew attention to “the importance of international humanitarian law.” Sometimes called “the law of war” or “the law of armed conflict,” this is described by the International Red Cross as “a set of rules that seeks, for humanitarian reasons, to limit the effects of armed conflict. It protects persons who are not, or are no longer, directly or actively participating in hostilities, and imposes limits on the means and methods of warfare.” 

In a strong message to states involved in war, though he did not name any, Pope Leo told the ambassadors that “Compliance with this cannot depend on mere circumstances and military or strategic interests.”

“Humanitarian law, in addition to guaranteeing a minimum of humanity during the ravages of war, is a commitment that states have made,” he said. “Such law must always prevail over the ambitions of belligerents, in order to mitigate the devastating effects of war, also with a view to reconstruction. We cannot ignore that the destruction of hospitals, energy infrastructure, homes and places essential to daily life constitutes a serious violation of international humanitarian law.”

Leo also condemned “any form of involvement of civilians in military operations” and said “the protection of the principle of the inviolability of human dignity and the sanctity of life always counts for more than any mere national interest.”

Freedoms violated

He reiterated the Holy See’s longstanding position in favor of multilateralism, and said its purpose is “to provide a place where people can meet and talk.” At the same time, he said, “in order to engage in dialogue, there needs to be agreement on the words and concepts that are used.”

Leo emphasized that “rediscovering the meaning of words is perhaps one of the primary challenges of our time. When words lose their connection to reality, and reality itself becomes debatable and ultimately incommunicable, we become like the two people to whom St. Augustine refers, who are forced to stay together without either of them knowing the other’s language.” 

In our culture today, he said, “the meaning of words is ever more fluid, and the concepts they represent are increasingly ambiguous. Language is no longer the preferred means by which human beings come to know and encounter one another. Moreover, in the contortions of semantic ambiguity, language is becoming more and more a weapon with which to deceive, or to strike and offend opponents.”

He told the ambassadors that to prevent conflict, “We need words once again to express distinct and clear realities unequivocally. Only in this way can authentic dialogue resume without misunderstandings.”

Next, he spoke about freedom of expression: “It is painful to see how, especially in the West, the space for genuine freedom of expression is rapidly shrinking. At the same time, a new Orwellian-style language is developing which, in an attempt to be increasingly inclusive, ends up excluding those who do not conform to the ideologies that are fueling it.” 

“Unfortunately,” he said, “this leads to other consequences that end up restricting fundamental human rights, starting with the freedom of conscience.” He mentioned here conscientious objection to military service and abortion and euthanasia. 

He also highlighted threats to religious freedom, noting “the most recent data show that violations of religious freedom are on the rise, and that 64 percent of the world’s population suffers serious violations of this right.” He told the ambassadors that “in requesting that the religious freedom and worship of Christians be fully respected, the Holy See asks the same for all other religious communities.” He reiterated the church’s rejection “of all forms of antisemitism, which unfortunately continues to sow hatred and death.”

He drew attention to the persecution of Christians, who “suffer high or extreme levels of discrimination, violence and oppression because of their faith. This phenomenon impinges on approximately one in seven Christians globally, and it worsened in 2025 due to ongoing conflicts, authoritarian regimes and religious extremism. Sadly, all of this demonstrates that religious freedom is ‘not considered a fundamental human right.’” 

At the same time, the pope said, “we must not forget a subtle form of religious discrimination against Christians, which is spreading even in countries where they are in the majority, such as in Europe or the Americas. There, they are sometimes restricted in their ability to proclaim the truths of the Gospel for political or ideological reasons, especially when they defend the dignity of the weakest, the unborn, refugees and migrants or promote the family.”

In a passage on migrants that is highly relevant to the United States at this moment in history, Pope Leo told the ambassadors, “It cannot be overlooked that every migrant is a person and, as such, has inalienable rights that must be respected in every situation.” He reminded them that many migrants “are forced to flee because of violence, persecution, conflict and even the effects of climate change.” He expressed the hope “that the actions taken by states against criminality and human trafficking will not become a pretext for undermining the dignity of migrants and refugees.”

War and peace

Turning to Ukraine, Pope Leo did not name Russia but reiterated “the pressing need for an immediate ceasefire, and for dialogue motivated by a sincere search for ways leading to peace.” He appealed to the international community “not to waver in its commitment to pursuing just and lasting solutions that will protect the most vulnerable and restore hope to the afflicted peoples” and expressed the Holy See’s “willingness to support any initiative that promotes peace and harmony.”

He next focused attention on the Holy Land, “where, despite the truce announced in October, the civilian population continues to endure a serious humanitarian crisis, adding further suffering to that already experienced.” He told the ambassadors—including those of Israel and Palestine—that “the two-state solution remains the institutional perspective for meeting the legitimate aspirations for both peoples; yet sadly, there has been an increase in violence in the West Bank against the Palestinian civilian population, which has the right to live in peace in its own land.”

He expressed “serious concern” at “the escalating tensions in the Caribbean Sea and along the American Pacific coast,” and, without mentioning the U.S. administration by name, he repeated his “urgent appeal that peaceful political solutions to the current situation should be sought, keeping in mind the common good of the peoples and not the defense of partisan interests.”

He said his last remark “pertains in particular to Venezuela, in light of recent developments,” alluding to the U.S. attack on that country and the capture of President Nicolás Maduro on Jan. 3. In this regard, he said, “I renew my appeal to respect the will of the Venezuelan people, and to safeguard the human and civil rights of all, ensuring a future of stability and concord.” 

Pope Leo also called attention to dire situations in Myanmar, Sudan, the Great Lakes region of Africa, Haiti and other places hit by armed violence and appealed for international efforts to help negotiate peace and a return to stability in these lands. 

In an important concluding paragraph, Pope Leo said, “At the heart of many of the situations I have mentioned, we can see something that Augustine himself pointed out, namely the persistent idea that peace is only possible through the use of force and deterrence.”

“While war is content with destruction, peace requires continuous and patient efforts of construction as well as constant vigilance,” he said. “Such efforts are required of everyone, starting with the countries that possess nuclear arsenals. I think in particular of the important need to follow up on the New START Treaty, which expires in February.”

He warned the ambassadors that “there is a danger of returning to the race of producing ever more sophisticated new weapons, also by means of artificial intelligence,” and said, “the latter is a tool that requires appropriate and ethical management, together with regulatory frameworks focused on the protection of freedom and human responsibility.”

The ambassadors warmly applauded when he finished speaking, and he then greeted each of them individually before going to the Sistine Chapel for a group photo.  

Gerard O’Connell is America’s senior Vatican correspondent and author of The Election of Pope Francis: An Inside Story of the Conclave That Changed History. He has been covering the Vatican since 1985.