A banner which reads 'Fall of Hong Kong Since 1997' (R) is carried during a protest march in Hong Kong on July 1, 2017, coinciding with the 20th anniversary of the city's handover from British to Chinese rule. China's President Xi Jinping warned July 1 that any challenge to Beijing's control over Hong Kong crossed a "red line", as thousands calling for more democracy marched through the city 20 years since it was handed back by Britain. / AFP PHOTO / Anthony WALLACE (Photo credit should read ANTHONY WALLACE/AFP/Getty Images)
