US President Barack Obama (C) listens to India's Prime Minister Narendra Modi (L) as they walk across a garden prior to a dinner banquet at the G20 Summit in Hangzhou on September 4, 2016. G20 leaders confront a sluggish global economy and the winds of populism as they open annual talks, but the long war in Syria and the South China Sea territorial dispute hang over the summit. / AFP PHOTO / JOHANNES EISELEJOHANNES EISELE/AFP/Getty Images