Pope Leo XIV has ignited debate among church leaders and peace activists by declaring ‘just war’ theory “outdated.”
Rather than functioning as principles of restraint, ‘just war’ theory has become a tool for justification.
“Today, more than ever …. the ‘just war’ theory, which has all too often been used to justify any kind of war, is now outdated,” the Pope wrote in his first papal encyclical, Magnifica Humanitas, released in May.
“Humanity possesses far more effective and capable tools for promoting human life and resolving conflicts, such as dialogue, diplomacy and forgiveness,” the Pope added. “The use of force, violence and weapons reflects a relational poverty that always has disastrous consequences for civilian populations.”
Rev. Peter Noteboom, general secretary of the Canadian Council of Churches, says the Pope’s position is “very significant.”
“Clearly, we are in a day when there is no such thing as ‘just war’,” he said.
The council, which officially represents most Canadian churches and about 80 per cent of Canada’s Christians, is organizing cross-country and cross-denominational reading groups this fall to discuss the full scope of the Pope’s 40,000-word encyclical.
The document includes arguments about how artificial intelligence and other technological advances have changed the nature of warfare.
“The Holy See has recently observed that the growing ease with which autonomous weapons systems can be deployed makes war more ‘feasible’ and less subject to human control,” the Pope wrote.
“[T]he development and use of AI in warfare must be subject to the most rigorous ethical constraints, to guarantee respect for human dignity and the sanctity of life and to avoid a race to develop such arms,” he added.
Deep roots
Western ‘just war’ theory has its roots in pre-Christian writing by the Roman General Cicero.
But it has been associated with Christian theology since the North African Bishop St. Augustine of Hippo wrote about it in the fourth century. Augustine’s thought on ‘just war’ was further systematized by St. Thomas Aquinas in the 13th century.
The theory was intended to set strict limits on the use of force by states. It sets out four conditions that must be met for war to be considered justified: a nation faces a serious threat of lasting harm; all other attempts at peace through diplomacy have been exhausted; there is a serious prospect of a defensive war succeeding; and the response must be proportionate.
When the current Pope says these principles are obsolete, this does more than incite controversy about Catholic theology, says Earl Turcotte, a former Canadian diplomat and past chair of the Canadian Network to Abolish Nuclear Weapons.
“The Pope’s views matter in the real world,” said Turcotte, who is also a veteran contributor to the Pugwash Conferences on Science and World Affairs, an international organization focused on reducing armed conflict.
“His stature gives him influence well beyond Catholics. Perhaps more than any other individual alive, people around the world look to him to establish and promote the standards of morality — standards that are, or should be, universal.”
‘Dramatic increases’
For Turcotte, the Pope’s statement on ‘just war’ theory should matter to Canadians as their defence budget is expected to ballon from two to five per cent of GDP over the coming decade.
“Many Canadians are incensed that Canada has accepted, even embraced, the NATO target, promoted mainly by the United States, of five per cent of GDP,” Turcotte wrote in an email to Canadian Affairs.
“Defence spending in Canada has traditionally been less than 1.5 per cent and only recently has hit two per cent. During Stephen Harper’s tenure it had fallen to just above one per cent … Even at two per cent, NATO’s collective defence budget is already 10 times that of Russia and five times that of China.
“Dramatic increases in defence spending by the West will only contribute further to the arms race.”
Mennonite theologian Jeremy Bergen says the Pope’s statement on ‘just war’ theory could open the way for Catholic-Mennonite co-operation in opposing the militarization of Canada’s budget, policies and culture.
“How can we do our part to steer things in a more peaceful direction, rather than say, ‘Well, we’re just not gonna get involved?’” said Bergen, who is also a professor at Conrad Grebel University, a Mennonite-associated college affiliated with the University of Waterloo.
“How can we push for development aid, and also make sure it’s used justly?”
Noteboom, of the Canadian Council of Churches, links the increase in defence spending to cuts in overseas development assistance and peacekeeping.
He queries why Canada’s 1970 commitment at the United Nations to spend 0.7 per cent of GDP on foreign aid should be taken less seriously than the newly minted NATO commitment to spend five per cent of GDP on the military.
“Wouldn’t that be our number one goal here, to get public funding for overseas development? And when I raise that, then I find that there’s some amnesia. People forget, or don’t know, those are strongly held as an expectation of Canada.”
Self-defence
Fr. Gordon Rixon, president of the University of Toronto’s Regis College, expects faculty and students at the Jesuit graduate school to spend a lot of the coming year studying and debating the Pope’s first papal encyclical.
Plans are already in the works for the college to lead a discussion about the encyclical in Toronto during the academic year.
Rixon and colleagues, including AI developer Sheldon Fernandez, last year presented a continuing education course on Catholic thinking about artificial intelligence, and the college convened an academic conference on the subject last winter. The encyclical encourages Jesuits to explore the practical implications of AI, including in war, Rixon says.
“You see a pretty consistent affirmation of the right of self-defence,” Rixon said. “With an acknowledgement that it is harder and harder to isolate a situation, given the technology of war…
“While there’s greater risk in the technology of war, there’s greater opportunity in communication and diplomatic resolution and creative thinking.”
The encyclical, addressed to “all the Catholic faithful, to all Christians and to all men and women of goodwill,” was never meant to be contained within debates about Catholic theology, Rixon says.
“He’s speaking to the world,” he said. “AI and its application in the technologies of war is a global, human concern.”
I sympathize with the Pope’s approach, but the fact is that Russia’s unprovoked invasion of Ukraine, and Trump’s abandonment of the rules-based international order has totally changed the global situation. As Canadians, it is apparent that we can no longer depend on America’s military might, as we did before, since America has turned from a trustworthy ally to a belligerent virtually overnight. There is a reality on the ground that we as a middle-power must acknowledge. Prime Minister Carney has been ahead of the curve in acknowledging this reality, and he is to be applauded for calling for cooperation between middle powers in the face of big power domination. In today’s world a “Turn the other cheek” policy is just not going to cut it.