America's long-term influence depends on its defense of an open, global society, writes The Economist: America must build a society that welcomes immigrants as well as trade. "America’s military dominance cannot last for ever," says The Economist's Lexington blog. "These days it is not only the world’s tired, poor huddled masses who yearn to breathe free. More often, it is the energetic and upwardly mobile. A fifth of China’s graduates say they want to emigrate; few peasants do. The open society needs defenders. So it would be nice if Mr Obama spoke up more often for the ideals etched on a certain statue."