Americans take pride in their "exceptionalism," not always aware that exceptional excess is part of the package. Compared to other wealthy countries, for example, America stands out as a gluttonous over-consumer: emitting twice as much carbon dioxide per capita as the average for the 27 nations of the European Union, and boasting obesity prevalence numbers that are double the industrial world average. But this is not all; America is also exceptional in the weakness of its national policy efforts to correct the challenges of obesity and climate change. For Paarlberg, these three failures -- in food and fuel consumption and policy response -- can be linked to the country's unusual material and demographic circumstances, singular political institutions, and unique political culture. American society is defined by the ideals of personal freedom and material abundance, conditions that elected leaders must always pledge to enhance, not diminish. Thus, as Paarlberg argues, democratic governments are unable to take effective preventative action against either climate change or obesity. Both crises will continue to worsen, forcing governments to gradually shift from their posturing of taking preventative action toward implicit acceptance and costly adaptation measures.

As Paarlberg shows in America's Excess, the US's pivot toward adaptation is important because it will produce dramatically unequal outcomes both at home and abroad. An effort to live with accelerating climate change may be feasible for the United States over a decade or two, when investments in adaptive technologies and infrastructures become affordable, but it will increase the vulnerability of poor countries that are unable to protect themselves. An American decision to live with obesity produces a different kind of inequity. It does little harm to foreign nations, but it will worsen outcomes for the obesity-prone segment of America's population, especially racial minorities and the poor.

Under such circumstances, and absent an unforeseen techno-scientific breakthrough in medicine or energy, the new challenge of good government will be to ensure equity between the wealthy and poor when making public investments to treat obesity or to protect vulnerable communities from extreme weather.