An assassin's bullet changed Ronald Reagan's life, but what about Donald Trump?

Not only did Pope Leo XIII collapse to the floor after celebrating Mass, but doctors couldn't find a pulse.

A priest who witnessed this 1886 drama testified: "His expression was one of horror and awe; the color and look on his face changing rapidly." When the pope regained consciousness, he described a hellish vision of Satan's plans to conquer the church.

In response, Pope Leo XIII wrote this prayer: "Saint Michael the Archangel, defend us in battle. Be our defense against the wickedness and snares of the Devil. May God rebuke him, we humbly pray, and do thou, O Prince of the heavenly host, by the power of God, cast into hell Satan, and all evil spirits, who prowl about the world seeking the ruin of souls. Amen."

For decades, Catholics recited this prayer after Mass, a practice continued by some Catholics and opposed by others. Thus, former President Donald Trump triggered debates by posting this prayer on social-media platforms on Sunday, September 29, the Catholic feast day of the archangels.

"Unless you're totally cynical and you think Trump was trying to appeal to the Catholic crowd before an election, you'd have to assume this had something to do with him coming millimeters from being killed by that bullet," said historian Paul Kengor of Grove City College, about 25 miles from Butler, Pennsylvania, the site of the July 13 assassination attempt.

"It's logical to ask how coming that close to death affects a man," stressed Kengor, whose book "God and Ronald Reagan" discussed the impact of Reagan's near death after a 1981 shooting. "Donald Trump has been a major figure in American life for years, and the public knows a lot about him. Will we see changes in his personality and his behavior, maybe even his faith?"

Trump has clearly, and repeatedly, said that he believes God spared his life.

Ties that bind: John Paul II, Ronald Reagan, Russia and Fatima

The world was buzzing with rumors about U.S.-Soviet talks as President Ronald Reagan flew to Italy for a global economic summit in the summer of 1987.

There were only two events on Reagan's schedule before the Group of Seven sessions -- a June 6 meeting with Pope John Paul II and a hush-hush briefing beforehand by U.S. Vatican Ambassador Frank Shakespeare.

The secret topic, at Reagan's request: The visions of Our Lady of Fatima to three children in Portugal in 1917, including prophecies linking St. Mary, Russia and, the world would later learn, the shooting of a "bishop in white." This was crucial information about John Paul II.

The pope believed Mary intervened to save his life on May 13, 1981, when an assassin tied to Bulgarian spies and Soviet military intelligence gunned him down in St. Peter's Square -- on the 64th anniversary of the first Fatima vision.

The pope needed six pints of blood to survive. Reagan required eight pints during surgery after he was shot six weeks earlier, on March 30th. He was convinced his survival was part of a divine plan, which Reagan called the "DP."

Reagan met John Paul II for the first time a year after the shootings. He told the pope: "Look how the evil forces were put in our way and how Providence intervened."

Clearly, the Soviet plans "backfired," said author Paul Kengor, in an Oct. 22 lecture at Walsh University in North Canton, Ohio.

"The Soviets were worried about an alliance. Right? So they wanted to end this alliance -- especially by getting rid of the pope," he said, speaking on the feast day of St. John Paul II.

Instead, these men went on to hold five strategic meetings, backed by an unknown number of back-channel contacts. Kengor's book about their friendship, "A Pope and a President: John Paul II, Ronald Reagan and the Extraordinary Story of the 20th Century," was published in 2017.

"Well, you really screwed this up," said Kengor, who teaches at Grove City College. "Now, these two -- they've got the world's most exclusive, mutual prayer society. They've got a bond that no pope and president may ever have."

There was no translator present in the 1987 Vatican meeting between Reagan and the multilingual John Paul II. The president told aides that they discussed U.S.-Soviet relations, nuclear arms control and Soviet leader Mikhail Gorbachev.

But in his public statement afterwards Reagan also included strong words about the future of Poland. John Paul II was days away from another trip to his homeland.