The significance of a global network of priests sank in for Thomas Reese on the day the president of Rwanda’s plane was shot down.

The Catholic analyst and author had been interviewing a church leader at the Vatican when his source’s phone rang. The call about the plane crash had been made to notify the headquarters of the Catholic Church that trouble was brewing.

“That was the beginning of an absolute disaster,” Reese said, referring to the 1994 Rwandan genocide that led to around 800,000 deaths.

By sitting in a Vatican office building, Reese learned of the assassination before millions of others. The call helped him understand why the Vatican is widely regarded as one of the best listening posts in the world.

“The Vatican has sources of information that the CIA would kill to get,” said the Jesuit priest, who is also chairman of the United States Commission on International Religious Freedom.

For that reason and others, the United States has sent an ambassador to the Holy See, a term that refers to the sovereign government of the Catholic Church, since 1984. American diplomats throughout the world benefit from the eyes and ears of the world’s largest faith, while the Vatican relies on U.S. military and economic might to aid in humanitarian crises.

This month, the Trump administration took steps toward soothing early tensions, nominating a new ambassador to the Holy See and planning the president’s first meeting with the pope, which will take place at the Vatican on Wednesday. More public clashes are likely, but the U.S. won’t risk a serious rift with one of its most important friends, experts said.

“Imagine a riot between Muslims and Christians in some village in Africa. If the U.S. wants to know what’s going on, (the government) could send a satellite overhead and tap everyone’s phones. But (Americans) probably couldn’t leave (their) embassy without a four-car caravan with armed guards,” Reese said. “The Vatican could call the bishop and the bishop could then call a pastor in the village and see what’s going on.”

Formal and informal relations between these two powers have led to a variety of interesting and even life-saving developments over the years.

One of the most famous examples involves the 1962 Cuban Missile Crisis and a letter from Pope John XXIII.

President John F. Kennedy, whose Catholic faith was a liability as a candidate, contacted the pope about the Soviet Union’s troubling presence on Cuba as he weighed military intervention. Nikita Khrushchev, the leader of the Soviet Union, swore that any interference would be met with force.

The U.S. and Soviet governments were on the brink of nuclear war when Pope John XXIII sent a note to their embassies urging them to stand down.

“He pleaded with them not to go forward with this confrontation,” Faggioli said, adding that both leaders acknowledged the role of the pope after the incident was resolved.

Another well-known event made possible by this “holy alliance” — documented by an article of the same name on the cover of Time magazine — was the fall of communism in Poland.

Throughout the 1980s, Reagan and Pope John Paul II worked together to destabilize the Soviet Union’s hold in the region. “Lech Walesa and other leaders of Solidarity received strategic advice — often conveyed by priests or American and European labor experts working undercover in Poland — that reflect the thinking of the Vatican and the Reagan Administration,” Time reported.

Most recently, Pope Francis worked closely with the presidents of the United States and Cuba to restore full diplomatic relations between the two nations and work toward open trade. He wrote letters to Barack Obama and Raul Castro urging friendship and then hosted delegations from both countries to iron out the details.

“I want to thank His Holiness, Pope Francis, whose moral example shows us the importance of pursuing the world as it should be, rather than simply settling for the world as it is,” Obama said as he announced America’s new Cuba policy in December 2014, according to CNN.

Vatican diplomats have changed the course of history hundreds of times through their relationships with world leaders, experts said.

“A lot of backdoor diplomacy occurs that people are not aware of,” Miguel Diaz, who served as U.S. ambassador to the Holy See from 2009 to 2012.

The next four years should be another interesting chapter in U.S.-Vatican relations.

“There are going to be significant areas of disagreement,” Diaz said, highlighting differing views on climate change, the refugee crisis and the availability of health care.

Full story at Deseret News.