GAZING from the Great Wall of China last week, US President Barack Obama appeared to be making the most of one of the perks of White House occupancy -- a private guided tour of Asia's most spectacular tourist spot. White House aides exulted that choreographed pictures of this moment would make front pages around the world. Yet an experience Mr Obama declared to be magical turned sour as he returned home to a domestic revolt that is fanning Democratic unease. It was not just that the US media have suddenly turned a lot more sceptical about a president with...