Florida Sen. Marco Rubio, shown here at an event in Washington last month, spoke with NPR's Morning Edition about the country's economic challenges. Molly Riley/AP hide caption

itoggle caption Molly Riley/AP

Prince Charles talks to Lynn Forester de Rothschild (left), organizer of the Conference on Inclusive Capitalism, and Christine Lagarde, head of the International Monetary Fund, before Tuesday's conference. The 250 corporate and financial leaders who attended control some $30 trillion, about a third of the world's investable assets. WPA Pool/Getty Images hide caption

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London's financial district, known as the Square Mile. Will it be one of the first dominoes to fall when society can no longer sustain itself? Peter Macdiarmid/Getty Images hide caption

itoggle caption Peter Macdiarmid/Getty Images