History is repeating itself at Europe's border, as migrants are desperately trying to make their way from Turkey into Greece. Many of these migrants come from Syria, where airstrikes have caused civilians to flee their country. Greek Minister of State Giorgos Gerapetritis joins Christiane to discuss his country's role in the crisis.

After 18 years of war, an Afghanistan peace deal created on Saturday is already falling apart. Today, the Taliban is launching more attacks on civilians and Afghan security forces. Simultaneously we're seeing the fate of Syria play out, as Russian president Vladimir Putin and Turkish leader Recip Erdogan meet in Moscow. Experts Vali Nasr and Susan Glasser join Christiane to discuss.

Dr. W. Ian Lipkin is an infectious disease expert at Columbia University who is fresh out of quarantine after traveling to China, where he was studying the coronavirus outbreak. The virus has now infected nearly 94,000 people around the world with more than 3,000 deaths. Lipkin sits down with Walter Isaacson to explain how the virus spreads and how people can avoid catching it.

"The Plot Against America," a new HBO series based on the novel by Philip Roth, re-imagines what the past would have looked like if Charles Lindbergh had won the presidential election of 1940 instead of President Roosevelt. Creator David Simon joins Christiane to explain the vision behind the series.

Joe Biden stormed through Super Tuesday with an impressive comeback, but he still has to fend off a formidable opponent in Bernie Sanders if he wants to win the nomination. Former Obama campaign manager David Plouffe joins the program to discuss the Super Tuesday results and the future of the Biden campaign.

The U.S. is segregated, and so is pollution. These words come from the so-called "father of environmental justice," Robert Bullard. As a sociologist, he has proved that minority communities in Houston suffer most from pollution and has written more than a dozen books on sustainable development, environmental racism and climate justice. He sits down with Walter to discuss his life's work.

Environmentalist Bill McKibben was one of the first to sound the alarm about climate change. His message to the public is simple: We have already done lasting damage to the planet, and we need to take urgent action before the situation becomes irretrievable. He joins the program to explain how divestment efforts are affecting the fossil fuel industry.

Combatting the climate crisis will require enormous individual change as well as drastic changes to our global economic model. When Paul Polman was CEO of consumer goods giant Unilever, he was one of the first titans of commerce to recognize the environmental issue. He joins the program to discuss the role of businesses in climate change.

Raul Ortiz joined the U.S. Border Patrol in 1991, and later served in Afghanistan. Now - thanks to President Trump -- he's the Border Patrol's new Deputy Chief. Over his career, he's been responsible for Border Patrol operations in 41 Texas counties and has witnessed families being torn apart at the border. He sits down with Walter to discuss this and President Trump's immigration policy.

On Saturday, the U.S. signed a deal with the Taliban that it hopes will finally end America’s longest war, the conflict in Afghanistan. Next week, the Afghan government will finally start negotiating face to face with the Taliban. Adela Raz, Afghanistan's Ambassador to the U.N., joins Christiane to explain this complicated process.

The coronavirus has killed more than 3,000 people and that number is rising rapidly. The World Health Organization has raised its risk assessment to "Very High" as a reality check and warning to every government in the world to contain the spread. Dr. Paul Offit, a Professor of Vaccinology at the University of Pennsylvania, breaks down the dangers of the virus.

Joe Biden has gained serious momentum heading into Super Tuesday. A comprehensive primary victory in South Carolina over the weekend coupled with the campaign suspensions of Pete Buttigieg and Amy Klobuchar may have wide implications as the centrists of the Democratic party coalesce around Biden’s candidacy. House Majority Whip Jim Clyburn joins the program to explain why he's endorsing Biden.

After this weekend’s South Carolina primary, Super Tuesday will separate winners from losers in the Democratic presidential race. 14 states will go to the polls March 3rd, including delegate-rich California and Texas. Right now, all eyes are on Texas to see whether this red state will turn purple as demographics shift. Journalist Jeremy Wallace joins Walter to discuss this battleground state.

The new film "Greed" tells the story of a disgraced billionaire. It's a thinly disguised version of the story of the British fast fashion mogul Sir Philip Green. He's accused of exploiting cheap labor in the form of South Asian garment workers to rake in billions for himself. Comedian Steve Coogan and director Michael Winterbottom join the program to discuss the film and the fast fashion industry.

In December, Myanmar's leader Aung San Suu Kyi was called before the international court of justice in the Hague and accused of government-sponsored genocide against Rohingya Muslims -- charges she denied. Historian Thant Myint-U joins Christiane to discuss this fraught situation and his new book "The Hidden History of Burma."

Award-winning journalist Aaron Glantz's latest book, “Homewreckers,” takes a shocking new look at America’s 2008 housing crisis. It’s a tale of greed and corruption, as Glantz pulls back the curtain on a group of Wall Street magnates who he says took advantage of a rigged system. Moreover, as Glantz tells Hari Sreenivasan, these “homewreckers” include key members of President Trump’s inner circle.

In France, a shocking story has shattered the image of a man once called a “living saint.” Jean Vanier was revered for his devotion to the disabled, yet the organization he founded, L’Arche International, revealed this past week that Vanier sexually abused at least six women over a period of 30 years. His biographer Michael Higgins joins the program to react to this news.

For the first time ever, there are now more new infections of coronavirus outside mainland China--where it originated--than inside, where it originated, and the world is scrambling to contain it. Tom Frieden was director of the Centers for Disease Control during the Ebola crisis, and joins the show to explain the severity of the crisis and how the U.S. should respond.

Congressman Dan Crenshaw of Texas was a Navy SEAL in Afghanistan eight years ago when he sustained a shrapnel injury to his eye. Thus healthcare is high on his list of priorities, especially because he lost his mother to cancer. Walter Isaacson speaks with Crenshaw in his home state of Texas about these and other election issues on his radar, as he faces his fight for re-election this November.

After being attacked from all sides at last night’s debate, Bernie Sanders is still standing and positioned as the strong frontrunner. But the criticisms came thick and fast from his fellow candidates, who slammed Sanders for his stance on guns and the price tag for his policies. His campaign co-chair Nina Turner joins the program to discuss whether the U.S. is ready for a Democratic socialist.