President Dilma Rousseff of Brazil faces a perfect storm, from charges of corruption to a slowdown in the economy.  The marches are frequent and getting more hostile: The ongoing corruption investigation of state-run energy company Petrobras may be her biggest problem, though.  Last week, the country's Supreme Federal Court approved investigations on 54 politicians, mostly from Rousseff’s Worker’s Party, suspected of being involved in a graft scheme with the oil giant.  Rousseff herself isn’t implicated in the scandal.  Even though she was chair of the Petrobras board at the time the alleged scheme occurred, she said she had no knowledge of any wrongdoing, and no evidence has surfaced implicating otherwise. Still, speculation about what she may have known has fueled the calls for impeachment. As the scandal unfolds, Rousseff’s popularity has sunk to an all-time low of 23 percent, according to a February survey by...(Read Full Post)