A trial began today in China that will prove to be the most politically importance since the prosecution of the Gang of Four in Beijing in the 1980s. The wife of ousted Communist Party official Bo Xilai is being tried for the murder of a British businessman.

The U.S. Ambassador to the U.K. Louis Susman talks about the mood in London, if the Games are a worthwhile investment, and the arrival of the First Lady and Mitt Romney in the city.

Although the fact that the surface of Greenland's massive ice sheet is melting is not news, the size and speed of the melt is. NASA scientists says a melt has taken place over a larger area than has been detected in three decades of satellite observation.

President Obama’s campaign continues its pressure on Romney to release his full tax records. If Bain’s SEC filings listed him as its chief executive from 1999 to 2003, they say, why did he claim to have left the company in 1999?

Americans will be able to test to see if they are HIV positive in the comfort of their own homes, thanks to the first over-the-counter FDA-approved test.

Barclays CEO Bob Diamond resigned this morning, the highest-profile casualty of an interest rate-rigging scandal that involves more than a dozen major banks around the world. The British banking giant is just one institution that is currently under investigation. 

Human Rights Watch has published details of what it says is a state policy of torture in Syria that amounts to a crime against humanity. It documents the locations of detention facilities and outlines the methods of torture used in them.

Contributors speak about how their lives will change when the Supreme Court rules on the Affordable Health Care Act today.

Losses from the bet "gone wrong" at JPMorgan Chase could total as much as $9 billion. Last month, chief executive Jamie Dimon said the bank had lost $2 billion on a dodgy bet on credit derivatives. But according to our partner The New York Times, that's just the tip of the iceberg.

The constitutional power grab by Egypt's military could trigger a review here of the money America gives to the country. In March, the Obama administration released more than a billion dollars in military aid, despite Cairo's failure to meet what's been described as pro-democracy goals.

According to a study released by the Pew Research Center today, Asians have passed Latinos as the largest wave of new immigrants to this country. The number of Asians in the U.S. quadrupled between 1980 and 2010 to about 18 million, or 6 percent of the total population. Researchers say the new numbers reflect both a slow-down in illegal immigration and the demands many companies are making for higher-skilled workers.

A government says it's worried about the legitimacy of the names on its voter lists. Rick Scott, the governor of Florida, is now in the middle of a blistering legal battle over Florida's attempt to purge as many as 182,000 from its voter roles. Marc Caputo is a political reporter for the Miami Herald.

The Russian government appears to be worried about a mass anti-government rally planned in Moscow today. People want to express their outrage directly at President Vladimir Putin for the first time since his inauguration. Yet Putin may be trying to preempt the rally with some intimidating moves of his own. Ellen Barry is the Moscow Bureau Chief for our partner The New York Times.

Nobel Prize winning economist and Columbia University professor Joseph Stiglitz responds to the bailout of Spanish banks. His new book is called the "The Price of Inequality: How Today's Divided Society Endangers Our Future."

The Justice Department has demanded that Florida stop trying to identify noncitizens to purge from its voter registration rolls. Last night the department sent a detailed letter to Florida's Secretary of State, Ken Detzner, instructing the state to end the practice, which it said violated the Voting Rights Act and the National Voter Registration Act.

New York City plans to ban the sale of large sugary drinks, announced Mayor Michael Bloomberg on Wednesday. The ban, which aims to fight obesity, would impose a 16-ounce limit on the size of sweetened drinks sold at restaurants, bodegas, and movie theaters. Joining us is Marion Nestle, professor of nutrition at New York University and author of "Safe Food: The Politics of Food Safety." Also with us is Jay Cowit, Takeaway Technical Director and Chief Soda Correspondent.

Last night in Florida, Secretary of State Hillary Clinton said U.S. specialists hacked into websites run by Al Qaeda’s affiliate in Yemen. The hackers were able to change online ads that boasted about killing Americans into advertisements that underscored the deaths of Muslim civilians in Al Qaeda terror attacks. We're joined by Jamie Doran, a producer for Frontline who worked on the new documentary "Al Qaeda in Yemen."

After a shaky debut, Facebook is getting off to a bad start on its first week of trading as a publicly held company. Facebook's stock is sinking nearly seven percent, falling below the $38 IPO price, in the social network's second day of trading as a public company Monday. Joining us is reporter for our partner the New York Times Michael de la Merced.

The fight between al-Qaeda and the Yemeni government continues this morning. At least 38 people were killed today when a suicide bomber attacked rehearsal for a military parade. There is also word that a member of the U.S. military was wounded today in what is being called an attack by Al Qaeda. Joining us from Sanaa is Reuters Correspondent Tom Finn.

We all know that we're living in the era of the super PAC. And we're now facing the first presidential election since the Supreme Court decision in the Citizens United case, the ruling that the American government couldn't stop political spending by large corporations and labor unions in election campaigns. According to our partner, The New York Times, there's a costly advertising plan underway to attack President Obama in ways never seen before.