Evaluating four acts of conspicuous leadership so far this week:

-Mayor Rahm Emanuel fired Chicago’s police chief yesterday. This was not especially surprising but gets more interesting as you look deeper. The issue of course was the furor sparked by video of a police officer last year shooting a black teen 16 times. Major protests in Chicago and acid criticism from around the country forced Emmanuel to act. But he had stood by police superintendent Garry McCarthy for four-and-a-half years as crime, and murders in particular, increased dramatically. And while you could call the firing a bold act of leadership, you could less charitably suspect it was a way for the mayor to ease the pressure on himself; he and the city’s lawyers had argued in court that the video should not be released. The bottom-line reality is that the firing had to be done.

–Pope Francis concluded his visit to Africa on Monday. He has made the plight of the poor a central focus of his papacy, and this visit took it further than ever. It’s one thing to visit the poor of Europe or Latin America, quite another to visit the Central African Republic, among the poorest nations on earth with per-capita annual GDP well under $1,000. In addition, the Central African Republic is a war zone. The pope’s dramatic actions do not alter church positions on any important issue. But they amplify his message and inspire admirers, and that’s effective leadership.

–Mark Zuckerberg and his wife, Dr. Priscilla Chan, yesterday announced the birth of their daughter and their intent to give away 99% of their fortune. What a convergence of events – you have your first child, you announce that during your lifetime you’ll give away virtually all of her potential inheritance, and you do it on Giving Tuesday, the four-year-old designated day for making charitable donations. I like the whole thing, mainly because it may inspire other mega-wealthy people to give away pretty much the whole boatload, as Warren Buffett and Bill Gates are doing. Zuckerberg’s Facebook shares are worth about $45 billion.

–Esau Marquez, a man whose name has probably never appeared in bold type before, made my favorite act of leadership so far this week, taking charge of a possibly deadly situation in San Francisco. Marquez is a bicycle deliveryman who on Monday heard people screaming on a sidewalk on Market Street. He observed a woman in a state of shock and blood on the sidewalk; a stabbing, he thought. Then he noticed an infant on the sidewalk. The woman had just given birth, and while others were standing around her yelling, no one was doing anything. Marquez immediately wrapped the baby in his jacket and slapped it on the back. It started breathing and crying. “Everyone was standoffish,” said a witness. “But he jumped in and probably saved that baby’s life.”

It’s today’s reminder that leadership is defined only by action, not by title or position or anything else.

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What We’re Reading Today

Yahoo considers spinning off core business

The company’s board is meeting to discuss Yahoo’s future, including whether to retain Marissa Mayer as CEO and whether to dispose of Yahoo’s core Internet business. Since the IRS won’t tell Yahoo in advance the tax implications of spinning off its Alibaba shares, worth over $30 billion, some investors have suggested selling the operating businesses, leaving Yahoo as just a holder of those shares. Mayer still seems to have strong support on the board. Fortune

Mark Zuckerberg will donate $45 billion

Announcing the birth of their first child, the Facebook CEO and his wife, Priscilla Chan, announced also they would give 99% of their Facebook shares – currently valued at $45 billion – to their charitable foundation through the course of their lives. By taking the Giving Pledge, Zuckerberg joins others, including Bill Gates and Warren Buffett, promising to donate nearly all their wealth to charitable causes. CBS News

Puerto Rico fights for bankruptcy protection

While Governor Alejandro García Padilla testified in Congress, pleading for bankruptcy protection for the struggling island, the country avoided its first major default by paying $354 million to creditors. But Padilla said the U.S. territory has run out of money and made this payment using funds for next month’s obligations, putting some Jan. 1 payments in jeopardy. NYT

Russia sneers at NATO’s tiny addition

NATO has formally invited the Balkan nation of Montenegro into the 28-nation military alliance. While the accession process could take a year, President Vladimir Putin warned that the move may provoke retaliation from Russia. Putin has long said he views any encroachment by NATO into former Communist territories of Eastern Europe as a threat to Russia’s interests. USA Today

Building a Better Leader

While solving an argument with a remote employee…

…move the conversation off email and involve a third party to weigh in. Harvard Business Review

Take risks at work

But make sure you do it in a way that others will understand by applying the rule of three and seeking the help of influential leaders. Fortune

Steve Wozniak credits mentors for his success

They include Steve Jobs and a high school teacher. BenefitsPro

Landing Attacks

U.S. increases presence in Iraq and Syria

To combat ISIS, Defense Secretary Ash Carter announced that he would deploy special operations forces in the two countries. In Iraq, an “expeditionary” group of 40, with 150 support personnel, will aid Iraqi forces and collect information. U.K. Prime Minister David Cameron will apparently win parliamentary approval to launch airstrikes in Syria as part of the anti-ISIS coalition. WSJ

Former Obama official: White House ignored ISIS intel

Former Defense Intelligence Agency chief Michael Flynn says President Barack Obama and his advisers ignored accumulating intel about ISIS in 2011 and 2012 because it didn’t help his reelection “narrative.” Obama has been criticized for his belief that ISIS wasn’t a credible threat, once calling it a “JV squad.” CNN

China blames criminals for U.S. hack

China’s official news agency, Xinhua, says an investigation into the hack of 22 million U.S. federal worker files found that criminals led the efforts, and it wasn’t state sponsored. It’s unclear if U.S. officials agree. The hack became a point of contention between President Obama and President Xi Jinping when the Chinese leader visited the U.S. in September. Reuters

Up or Out

Jeffrey Housenbold will step down as Shutterfly CEO in February. Business Wire

Jay Z‘s music streaming service Tidal has named Jeff Toig its new CEO. Fortune

Fortune Reads and Videos

Sheryl Sandberg for President?

Hillary Clinton and Carly Fiorina shouldn’t be the only female candidates. Fortune

Patent lawsuits set one-day record

On Monday, 257 suits were filed; 37 came from one company. Fortune

Starbucks pulls turkey panini from 1,347 shops…

…in response to an E. Coli scare. Fortune

Credit scores replaced by Facebook profiles

Startups are using social media to assess creditworthiness. Fortune

Happy Birthday

Senate Minority Leader Harry Reid turns 76 today. Biography

Retired NBA basketball player Jason Collins, the first openly gay athlete to play in one of North America’s four major professional sports, turns 37. Biography

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