Papal security: How Catholic leader is kept safe

(CBS News) Keeping the pope safe is no easy task. Unlike most world leaders, being among the masses and tending to the faithful is a job requirement. So how do you protect the spiritual leader of more than one billion Catholics? It requires a mix of modern-day measures and centuries-old security.

For heads of state, protection from those who would wish them harm is a way of life. But the head of Vatican state is a man who demands to be accessible to crowds -- to touch and be touched. Security has to be discreet

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Phillip Pullella, a Vatican correspondent for Reuters, said, "I think it is much more dangerous to be pope than, say, it is to be the United States president or president of any country."

During his time as pontiff, Pope Benedict XVI was occasionally left exposed. In 2009, a young woman caused the elderly pope to fall as he walked through St. Peter's Basilica to celebrate Mass. It turned out to be nothing more sinister than misplaced devotion. And a breach in 2011 was more Kodak moment than life-threatening when a child ran up to the pope.

Pullella, who traveled extensively with Pope John Paul II, remembers the day that pope's life was almost lost and the lives of all future popes changed.

"On May 13th of 1981, John Paul was riding in what became known as the Popemobile," Pullella recalled. "In fact, was just a white Jeep. And he was standing there and he was shot by Turkish gunman Mehmet Ali Agca, and he nearly died. He came within a hair of dying."

A plaque marks the spot on the floor of the Vatican hospital where Benedict's predecessor was resuscitated.

But keeping the head of the Catholic Church alive and well had been on the agenda way before 1981. In the 13th century, the Passetto Di Borgo -- a secret passage -- provided a quick getaway to any pontiff whose Vatican came under attack. It runs from the back of the basilica, along the aqueducts of Rome, to the safety of the Castel Sant'Angelo. A must-see for Rome's tourists, these days it's not as secret as it used to be.

But history is everywhere: The Swiss Guard -- one of the oldest, and certainly the most colorful -- armies in the world, have been looking after popes for more than 500 years.

But modern crowds require modern measures. The ancient structures of the Vatican now surrender themselves to high-tech surveillance systems.

No sooner did the conclave start than curious crowds made their way to St. Peter's Basilica. There were just a few hundred people, but Rome's police is preparing for numbers to rise to hundreds of thousands, probably within hours, should an Italian get the vote. It's about more than keeping the pope safe; it's about keeping everyone safe.

Whoever he is, the new pope inherits a Catholic Church demanding change, but some things will stay just as they are.

Pullella said security for the new pope will be "more of the same." Why? He said, "You can't be ... a bulletproof pope."

For more on papal security, watch the video in the player above.