Every page is packed with thought-provoking facts and ideas (which is why ploughing through 528 pages has taken me so long.) As a piece of popular anthropology this is perhaps unnecessary: half of the case studies would have been quite enough to support the author's main thesis, that short-termist decisions (especially on environmental issues) can be catastrophic for societies. But it's worth reading right through to the strong conclusions:
Because we are rapidly advancing along this non-sustainable course, the world's environmental problems will get resolved, in one way or another, within the lifetimes of the children and young adults alive today. The only question is whether they will become resolved in pleasant ways of our own choice, or in unpleasant ways not of our choice, such as warfare, genocide, starvation, disease epidemics, and collapses of societies. While all of those grim phenomena have been endemic to humanity throughout our history, their frequency increases with environmental degradation, population pressure, and the resulting poverty and political instability.
Examples of those unpleasant solutions to environmental and population problems abound in the modern world and the ancient world. The examples include the recent genocides in Rwanda, Burundi, and the former Yugoslavia; war, civil war, or guerilla war in the modern Sudan, Phillipines, and Nepal, and in the ancient Maya homeland; cannibalism on prehistoric Easter Island and Mangareva and among the ancient Anasazi; starvation in many modern African countries and on prehistoric Easter Island; the AIDS epidemic already in Africa, and incipiently elsewhere; and the collapse of state government in modern Somalia, the Solomon Islands, and Haiti, and among the ancient Maya. An outcome less drastic than a worldwide collapse might "merely" be the spread of Rwanda-like or Haiti-like conditions to many more developing countries, while we First World inhabitants retain many of our First World amenities but face a future with which we are unhappy, beset by more chronic terrorism, wars, and disease outbreaks. But it is doubtful that the First World could retain its separate lifestyle in the face of desperate waves of immigrants fleeing from collapsing Third World countries, in numbers much larger than the current unstoppable influx.
This book is a fascinating introduction to a wide variety of civilisations, and has really opened my eyes to how societies establish and maintain themselves. Highly recommended, if you have the time!