20 years on, how have the September 11  attacks ruptured America’s sense of safety and plunged the West into a “war on terror”?

Following a jaunty ceremony featuring a 21-gun salute, folk dancers and Gangnam Style star Psy, Park Geun-hye, who was sworn in on Friday as president of South Korea, made a revolutionary promise - to make her workaholic, ultra-competitive, ultra-stressed people happy.