The day before President Trump met with Pope Francis, Cardinal Peter Turkson juxtaposed the president’s speech in Saudi Arabia with what the Pope said in Egypt.

Taking to Twitter, he wrote: “Pope Francis & Pres Trump reach out to Islam-world to exorcise it of [religious violence]. One offers peace of dialogue, the other security of arms.”

Which seems fitting. It would be odd for a pastor to counsel recourse to arms. Similarly, it is expected that a commander in chief would seek to augment security through arms.

Cardinal Turkson’s tweet thus could be read as a mere observation that a spiritual power is doing what a spiritual power does, and a military power is doing what a military power does.

Yet the Ghanaian cardinal, Francis’ chief “minister” for matters of justice, peace and development, likely intended something more than that. He was suggesting that the “peace of dialogue” is the path to be preferred over the “security of arms.”

Is that correct? Surely it is, calling to mind Sir Winston Churchill’s remarks at the White House in 1954: “It is always better to jaw-jaw than to war-war.”

Churchill knew well the necessity of war, and also the horrors of it. To those who might tire of the jaw-jaw of apparently fruitless diplomacy, the great wartime leader countered that war-war was far worse. The Holy Father made the same argument more eloquently in Cairo.

“An education in respectful openness and sincere dialogue with others, recognizing their rights and basic freedoms, particularly religious freedom, represents the best way to build the future together, to be builders of civility,” Pope Francis said. “For the only alternative to the civility of encounter is the incivility of conflict; there is no other way.”

The Holy Father has put dialogue at the heart of his papal diplomacy. It is his constant refrain and exhortation.

Does it work? Or does the “peace of dialogue” have limits beyond which the “security of arms” must be employed?

A good case study might be the first Gulf War.

After the Iraqi invasion of Kuwait, St. John Paul II repeatedly called for a diplomatic solution, inveighing against coalition military action against Saddam Hussein. Clearly, a peaceful withdrawal by Hussein would have been the best solution, and if that was possible through peaceful dialogue, it would be the favored course of action.

Yet peaceful dialogue can also be a stalling tactic while an aggressor consolidates his gains. And if it is clear that an unjust aggressor has no intention of change, then a commitment to dialogue alone can become a tacit toleration for aggression or oppression.

During the debate over the first Gulf War, that was precisely the question that various world leaders had to evaluate. What could be achieved through peaceful dialogue? Was the invasion of a neighbor with intent to annex it already an indication that Hussein was not interested in dialogue? Did the injustice inflicted upon the suffering people put a limit on the time for dialogue? Did the Holy See’s advocacy for the peace of dialogue create confusion, creating a moral equivalence between the invaders and those who sought to repel them?

The passage of time permits those types of questions to be answered with greater clarity.

The current situation is, of course, less clear.

Pope Francis has certainly called for dialogue to resolve world crises, placing the peace of dialogue at the heart of his papal diplomacy. How has it fared?

A clear success that Vatican officials point to would be the Obama-Castro agreement in December 2014 that led to a resumption of diplomatic relations between the United States and Cuba. The back-channel negotiations that led to the agreement were facilitated by the good offices of Pope Francis, who wrote to both leaders as part of getting the dialogue started.

After more than 50 years of a stalemate, the prospect of normalization of relations arose from that dialogue.

Critics of the Castro regime point out that since the 2014 breakthrough, human-rights abuses have continued and in some cases worsened. Was that the price of getting the Cubans to talk?

The Holy Father also gave his support to the negotiations in Colombia that ended that country’s long civil war. While the peace agreement failed to win in a national referendum, due to criticism that it let the FARC rebels off too easily, it has since been implemented through executive action.

In response to such criticism, the Holy Father’s apparent position was that without such a dialogue, even if it lacked full justice, the war would not end. The alternative to encounter, as the Holy Father says, is continued conflict.

Pope Francis will travel to Colombia later this year to express his support for the cease-fire; he will likely, on that occasion, expand upon the possibilities offered by the peace of dialogue.

The tensions on the Korean Peninsula have raised fears about possible war. The new president of South Korea, Moon Jae-in, a Catholic, just sent a special envoy to Pope Francis, asking for the Vatican’s help in reducing tensions with North Korea.

Clearly, the Holy Father’s advocacy of dialogue resonates. Would such a dialogue be engaged sincerely by the North Korean regime?

There have been three principal conflicts that Pope Francis has faced, and he has advocated dialogue as the proper resolution of all three: Syria, Ukraine and Venezuela.

Here, a different picture emerges. All three situations have deteriorated, with the principal dictators — Bashar Assad, Vladimir Putin and Nicolas Maduro — not only unrestrained by dialogue, but in fact employing it as a tactic to solidify their ill-gotten gains.

In Venezuela, the situation is most galling, as Maduro has argued that the Holy Father’s call for dialogue puts the Pope on the side of the regime, while the local bishops are being “disobedient” to Rome in siding with the people. The local bishops respond that sincere dialogue is not possible with a dictator who is actively killing his people by direct violence and starvation.

The world does not need the Holy Father to be a cheerleader for the recourse to arms, let alone war. Yet there are evils about that seem immune to the diplomacy of dialogue.

The pontificate of Pope Francis is helping to clarify in practice where those limits are, in both the successes and failures of papal diplomacy.

Father Raymond J. de Souza

is editor in chief of Convivium magazine.