I spent 4 days at the Expo. Never seen any fair of this massive scale. More than 200 countries participated, i.e., almost all UN members (except for Vatican, Bhutan & Burkina Faso) plus some political entities such as Cook Islands, Niue, French Polynesia and Palestine. It's like all the nations of the world paying tribute to the new superpower on Earth. China probably subsidies the attendance of the small and poor countries in an attempt to show that all nations far and away are here. This is no different from the old days when states around China send a few exotic products to the Chinese emperor as tributes and received in advance treasures and gold with value well in excess of what they brought to the Chinese. But these gave the emperors tremendous prestige and domestic veneration. It is an act of power and self-validation. Has this changed?