One of the most influential living photographers today is American James Nachtwey, who had captured tumultuous events in South Africa, Latin America, the Middle East, Russia, Eastern Europe, and the former Soviet Union. He shot pictures of war, conflict and famine, and images of socio-political issues (pollution, crime and punishment). He won coveted Robert Capa Gold Medal an unprecedented 5 times.
Nachtwey was one of the first photographers to respond to the events of 9/11 because he lives just a few blocks away from the World Trade Center site. His above photo captures the moment when the South Tower collapsed; even in that early moments of War on Terror, Nachtwey saw the comforting presence of a religious icon and also the conflict between the Judeo-Christian West and the Islamic Middle East. The photo was the centrepiece of his photoessay, Shattered.
See his TED talk here.