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German Catholic News Agency KNA via Getty Images file

Joseph Ratzinger gives a theology lecture at the University of Freising in Germany during the summer semester in 1955.

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Published at 5:21 p.m. ET: Pope Benedict XVI always said he was first and foremost a teacher and a writer, and in his retirement he intends to pick up where he left off before he was called to church leadership, the Vatican said Monday. But is that a realistic expectation for a man universally known for his restless and questing intellect?

Roman Catholic Church law doesn't extensively account for a pope's abdication — among the hundreds of thousands of words in the Code of Canon Law, there's just one sentence: "If it happens that the Roman Pontiff resigns his office, it is required for validity that the resignation is made freely and properly manifested but not that it is accepted by anyone."

And since that hasn't happened in almost 600 years (or in more than 700 years depending on how you interpret history), there's no precedent for just what role, if any, a living ex-pope plays in the church.

What little is known came in a brief statement Monday from the Vatican, which said that when he leaves the papacy on Feb. 28, Benedict would move to Castel Gandolfo, the pope's summer residence in the Alban Hills a few miles south of Rome. Eventually, he will take up residence in a former cloistered monastery in the Vatican. What he will do there hasn't been clarified, but when he was elected pope in 2005, he said the job had interrupted his plans to retire and spend the rest of his life writing "in peace and quiet."

Beyond its obvious authority, the papacy is unique within the Catholic Church because of its temporal status — it doesn't come with the equivalent of tenure. So the moment he steps aside, Benedict will return to being just Joseph Aloisius Ratzinger, with no special authority or official prerogatives. 

"This is all very new territory," said Donald S. Prudlo, a historian at Jacksonville State University in Alabama and scholar of theology and church history at the Notre Dame Graduate School of Christendom College in Front Royal, Va. "No set of guidelines exist for an ex-pope, even including where he should live, what he should be called and what liturgical role he would play."

It's not even certain that Benedict will resume being an active cardinal — that would be up to the new pope. Prudlo told NBC News he thought it was "unlikely," saying he expected Benedict would want almost no public visibility in his declining years.

Even if Benedict, 85, does resume life as Cardinal Ratzinger, he's beyond the cutoff age of 80 to be eligible to vote, meaning he'll be locked out of the room when the College of Cardinals elects his successor as the leader of more than 1.2 billion Roman Catholics around the world.

But that doesn't mean he won't have influence should he choose to exercise it, and that could be tricky for his successor, said John Thavis, Rome bureau chief of Catholic News Service.

"The church has not really had a situation of two popes in many centuries," Thavis told NBC News from Vatican City. 

One reason is that the church has historically discouraged papal abdication out of concern about divided loyalties. Benedict's predecessor and mentor, John Paul II, declared that "there cannot be an 'emeritus pope.'"

"It is going to be hard for people to forget that Pope Benedict is still alive and he is still perhaps writing, still perhaps expressing himself," Thavis said. "I think it's going to fall to his successor to find a way to utilize this kind of expertise perhaps in a way that does not create new difficulties for the church."

But George Weigel, a Catholic theologian at the Ethics and Public Policy Center, a nonprofit religious research foundation, said Benedict "understands there is not room in the church for two popes."

"He will be very discreet about even writing new books," Weigel told NBC News.

Prudlo also predicted a smooth transition — perhaps the most orderly in centuries — because Benedict will be there to give the new pope the lay of the land.

"A new pope is often left flummoxed by the ins and outs of the office, usually taking years sometimes to gain a foothold," Prudlo said. "Having a 'senior pope,' for lack of a better word, would prove invaluable to easing into the throne of Peter."

Tracy Connor of NBC News contributed to this report.

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Updated at 10:27 p.m. ET: Two former Navy SEALs were identified Thursday as the third and fourth victims of the attack on a U.S. consulate in Libya this week that also killed the U.S. ambassador.

U.S. officials and family members identified the men as Glen Doherty, 42, a native of Winchester, Mass., and Tyrone S. Woods, 41. Details of how they died haven't been made public.

The men were working as private security specialists for the U.S. government when militants attacked the U.S. Consulate in Benghazi on Tuesday night. In all, four Americans were killed; the others were previously identified as the U.S. ambassador to Libya, Christopher Stevens, and Sean Smith, an information management officer.

Libyan authorities said Thursday that they had arrested four men in connection with the attack but gave no further details.

In a statement Thursday evening, Secretary of State Hillary Rodham Clinton said Woods was known to his family and friends as "Rone" that and they they relied on "his courage and skill, honed over two decades as a Navy SEAL."

Woods, who was also a registered nurse and certified paramedic, served several tours in Iraq and Afghanistan and had been protecting U.S. diplomatic personnel in dangerous posts from Central America to the Middle East, Clinton said.

He was married to a dentist named Dorothy and had three sons: Tyrone, Jr., Hunter and Kai, who was several months old.

Defense Department records listed Wood's residence as Portland, Ore., but NBC station KNSD of San Diego and numerous other reports from the area said he lived in Imperial Beach, Calif., where he settled after leaving the Navy and for a time owned a pub called the Salty Frog.

His death was confirmed by his ex-wife, Patty So of San Diego, who was notified by the U.S. government.

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"He was the greatest Navy SEAL. Nobody was more skilled than him," said So, the mother of Woods' two teenage sons. "He loved being a SEAL more than life itself."

Doherty — known to friends and family as "Bub," according to Clinton — was described as a highly trained marksman and security expert who "lived life to the fullest." He was also an experienced paramedic.

"Glen lived his life to the fullest. He was my brother, but if you asked his friends, he was their brother, as well," his sister, Katie Quigley of Marblehead, Mass., said Thursday.

Doherty joined the Navy in his late 20s after having attended flight school and worked as a ski instructor. A skilled pilot, master marksman and medical corpsman, Doherty was a member of the elite Sea, Air and Land (SEAL) special operations corps for nine years before he left the Navy in 2005.

Kokoro Camp Trainer of Encinitas, Calif., where Doherty worked as a fitness trainer, said that as a civilian, Doherty continued to take assignments in security and intelligence for various U.S. government agencies, serving in Iraq, Lebanon, Pakistan and Afghanistan, as well as Libya.

In Libya, Doherty "was protecting the ambassador and also helping the wounded" when he was killed, Quigley said.

Doherty co-wrote the book "21st Century Sniper: A Complete Practical Guide" with another former SEAL, Brandon Webb, who called him "one of the finest human beings I've ever known."

"He died serving with men he respected, protecting the freedoms we enjoy as Americans and doing something he loved," Webb said.

In 2009, Doherty was featured in an episode of the NBC-TV reality series "The Wanted," in which intelligence and military experts and investigative journalists sought to track down suspected terrorists.

In the episode, Scott Tyler, a fellow former SEAL, endorses Doherty's marksmanship and describes him as "highly recommended from people I trust in my community."

Doherty and other operatives hunted a suspected terrorist in Norway for extradition to Iraq. Doherty devised the surveillance plan, using miniature cameras hidden outside the suspect's home in Oslo.

Doherty was interviewed on screen discussing surveillance techniques and the importance of maintaining focus in a dangerous situation.

It's "a good thing to just read all of the people in the neighborhood and just try to be hyperaware of what's happening," he said. "It's not like you see on TV ... You focus on the mission. That's it."

Quigley said the attack on the consulate had to have been extremely violent and well-coordinated, because "Glen was highly trained. He was the best of the best."

"This was serious, well-planned, well-executed," she told NBC station KNSD-TV of San Diego. "He was very good at what he did."

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When President Barack Obama arrived Tuesday in Afghanistan on the first anniversary of the killing of Osama Bin Laden, it was supposed to be a secret, like his earlier visits to the dangerous region. But news of the trip leaked out hours earlier, raising new alarm bells about the president's security.

The Afghan news station TOLONews reported early Tuesday that Obama had arrived in Kabul, hours before the White House's embargo on reporting the news was lifted. Other news organizations, including The New York Post and the official Chinese news agency, Xinhua, cited that report, which was attributed to unnamed Afghan officials.

The U.S. National Security Council and the U.S. Embassy in Kabul both denied the report, and Obama's official schedule indicated that he was still in Washington, meeting with Defense Secretary Leon Panetta in the Oval Office:

President Barack Obama's official schedule for Tuesday indicated that the president was remaining in Washington all day.

In fact, he had left Joint Base Andrews, Md., aboard Air Force One shortly after midnight Tuesday morning.

M. Alex Johnson is a reporter for msnbc.com. Follow him on Twitter and Facebook.

In the face of the official denials, the Post removed its report, as did Buzzfeed, which deleted a tweet noting the news after an NSC official called it to argue that its report endangered Obama's life, it said.

Obama's previous visits to Afghanistan, in March and December 2010, were unannounced for security reasons, and news of them didn't leak out. And strict security measures were in place Tuesday as well, including a White House embargo that prevented journalists traveling with the president from reporting the trip until Obama arrived at the Afghan Presidential Palace about 11:30 p.m. (2:30 p.m. ET), hours after the TOLONews report was published.

But this time the news did get out, and at an uncomfortable time for U.S. security officials.

The apparent breach comes in the wake of an incident last month in which members of the president's advance security team were reported to have picked up prostitutes in Cartagena, Colombia, before Obama's visit to the Summit of the Americas. Eight Secret Service agents have been forced to leave the agency as a result of the scandal.

The Defense Department said it couldn't discuss the incident, and the White House didn't immediately return calls for comment. Editors at TOLONews did not respond to an email seeking comment.

Ronald Kessler, a longtime political reporter who interviewed more than 100 active and former Secret Service agents for "In the President's Secret Service," a book on presidential security arrangements, told msnbc.com that an early report on a surprise visit "clearly endangers the president when he's going into a war zone."

The biggest concern, he said, "is the possibility of attacks on the ground when (Obama) lands and thereafter."

NBC News and other news organizations learned about the trip Tuesday but withheld reporting it until Obama arrived at the palace. But "the fact so many U.S. reporters knew about it made it easier for it to disseminate," Kessler said.

Kessler suggested that the Obama administration follow the example of the administration of former President George W. Bush, "which did not let reporters know beforehand at all" when Bush traveled to Afghanistan.

"They told the press pool that they were going to go on a trip, (but) they weren't told where," Kessler said. "It was not until they got on the airplane that they were told they were going to Afghanistan."

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With parliamentary elections scheduled for next week, Iran has begun blocking Internet services, Web security experts say, adding to concerns that government leaders hope to shut off Iranians from the rest of the online world.

M. Alex Johnson is a reporter for msnbc.com. Follow him on Twitter and Facebook.

The Tor Network, which provides free software for anonymous use of the Internet, reported that on Feb. 9, Tehran began filtering keywords and throttling or shutting down access to sites that use a form of security called Secure Socket Layers, or SSL. The protocol, which encrypts data being sent back and forth between servers and users, is used by such popular sites as Gmail and Facebook. Web addresses protected by SSL begin "https," instead of "http."

Activists in repressive countries often use Tor services to get around such restrictions, and before Feb. 9, Iranians were the second-largest users of Tor. But because Iran targeted the core SSL protocol, "Tor stopped working too," the organization said.

The action is blocking email and some Web access for as many as 30 million Iranians who use SSL-protected sites, reported CBR Systems & Network Security, a European technology organization.

Iran, which will hold parliamentary elections on March 2, has referred to Google and other search engines as "spying tools," and it has throttled access to foreign web servers previously at politically sensitive times. The free-expression activist group Reporters Without Borders has branded Iran as an "enemy of the Internet." (.pdf)

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Iran's Communications and Technology Minister Reza Taghipour said Monday that a firewalled "national Internet," which Tehran has been promising since as early as 2006, would be launched in the spring. Internet security analysts and open-Internet activists say the "national Internet" would act as a closed intranet sealing Iranians off from large chunks of the web. Similar systems are known to be in use in China and North Korea. 

The Iranian news agency Mehr quoted Taghipour as saying at a cyberdefense forum in Tehran that "the first phase of this network will become operational in the month of Khordad," which straddles May and June. 

The Tor network said it was continuing "to research and investigate solutions with the assumption that SSL will eventually be blocked nationwide inside Iran." 

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Adolf Hitler purportedly fathered Jean-Marie Loret in 1917 with a 16-year-old French mistress.

New evidence has emerged to support the disputed theory that Adolf Hitler had a secret son in 1918 after an affair with a teenage French mistress, a French newsmagazine reported Friday.

The man, Jean-Marie Loret, died in 1985 after an eventful life that saw him join the French Resistance and fight German forces led by the man who the evidence suggests was his father. 

Loret claimed to be Hitler's son in an autobiography he published in 1981. The claim has been hotly debated by historians ever since, with the weight of opinion concluding that the story was bunk.

M. Alex Johnson is a reporter for msnbc.com. Follow him on Twitter and Facebook.

The new evidence — which includes handwriting analysis, documents indicating Hitler secretly supported the woman financially and paintings signed "Adolf Hitler" discovered in her home — is outlined by Le Point magazine, whose report Friday was widely picked up in the French media but largely ignored by German news outlets.

The evidence comes from Loret's lawyer, Francois Gibault, who said Loret's children could use it to establish a claim to royalties from Hitler's manifesto, "Mein Kampf."

Loret's 30-year-old autobiography is also expected to be republished to include the new evidence.

Loret's mother, Charlotte Lobjoie, was 16 when Hitler, who was a corporal serving with German forces in France in World War I, supposedly had an affair with her while on leave in 1917. 

Loret wrote that his mother told him that she was working in a hayfield in Fournes-en-Weppe with other young women when they spotted the young soldier drawing on a sketch pad across the street. She was chosen to go ask him what he was doing.

"He was attentive and friendly," she told her son, and that sparked a relationship that lasted several weeks.

Read the Le Point story (in French)

Le Point writes:

One evening in June 1917, returning a little drunk from a night out with a friend, he [Hitler] got frisky with Charlotte. In March of the next year, a son was born. ...

Years passed, and Charlotte refused to talk about the mysterious circumstances of her son's birth. Destitute and vaguely shamed, she gave up custody of her son to another family in 1934.

His "real father" refused to see him but continued from time to seek to ask for news about him from his mother. 

A few weeks before she died in the early '50s, Charlotte confessed to her son the true identity of her father. The shock was terrible.

In his 1981 book, "Your Father's Name Was Hitler," Loret wrote: "In order not to fall into anxiety, I worked tirelessly, never taking vacation — 20 years without going to a movie."

Le Point quoted Guibalt on Friday as saying that during the 1970s, however, Loret began seeking evidence of his parentage. He hired several experts: a historian, who visited his childhood home and questioned witnesses; a geneticist from the University of Heidelberg, who compared Hitler's and Loret's blood types; and a handwriting analyst, who compared their writings. 

"All reached the same conclusion," Le Point reported. "Jean-Marie Loret was probably the son of Adolf Hitler."

See the handwriting comparison published by Le Point (.pdf)

"When he came to me in 1979, I had before me a lost man who did not know whether he wanted to be recognized as the son of Adolf Hitler," the magazine quoted Guibalt as saying.

"He experienced the feelings of many illegitimate children: the desire to discover his past, but also a fear of the old memories. I talked with him a lot, playing more the role of a psychologist than a lawyer," Guibalt said.

The magazine reported that the new evidence includes paintings signed "Adolf Hitler" — Hitler was a painter before going into politics — that were discovered in the attic of Lobjoie's home, as well as a Hitler-signed portrait of a woman believed to be Lobjoie that was discovered in Germany.

It also includes documents that Le Point said establish that officers of the Wehrmacht, the German armed forces, hand-delivered envelopes of cash to Lobjoie during the German occupation of France. 

Loret, meanwhile, was with Resistance forces at the Maginot Line in 1939, Le Point reported, and in 1940, his unit fought a fierce battle against German troops in the Ardennes. During the German occupation, Loret worked as a Resistance spy under the name "Clement," it said.

Now, Gibault said, Loret's children could have a claim to royalties from "Mein Kampf," the philosophy of which Loret fought bitterly during World War II.

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