Maria Corina Machado - Venezuelan opposition politician

Two years after the death of Hugo Chavez, Venezuela's socialist revolution is in trouble. The country's oil-reliant economy is ravaged by inflation, shortages and corruption. Those hit hardest are the poor, Chavez's bedrock supporters. Stephen Sackur speaks to one of the most prominent and outspoken members of the Venezuelan opposition, Maria Corina Machado. How close is chaos in Venezuela?