The idea that the United States is in a state of rapid, fundamental decline is now widely proclaimed. What started as speculation has in recent years become a chorus of voices and is now a pervasive din. Columnists, classical historians, international economists, European allies, Chinese generals, and the wider blogosphere pronounce and repeat the idea. For some, the transformation is welcomed and embraced, for others it is expressed with deep concern, but there can be little doubt that the notion is widely shared.

The description is driven by America's difficulties overseas and at home. The frustrations and costs of long wars in Afghanistan and Iraq, a continuing campaign against radical Islamist terrorism, the rise of China and of other emerging powers, and the challenges of coping with globalization and growing economic competition suggest that the United States has become overextended and is no longer capable of playing a leading role in world affairs. At home, the collapse of the real estate bubble, followed by financial crisis and a great recession, a lagging recovery, and destructive partisanship in the face of deepening problems of debt and deficit have led to gloomy assessments about America's economy, politics, and society.