A greatly compelling book that articulates a fairly systematic and evidence-based understanding of what causes social collapse. Some further reading suggests he may have had a few of the facts wrong here or there, or that he should have looked more closely at some of the interpretations he had, but overall it's a solid work as far as I can tell.

It's also received a lot of criticism from certain quarters, and they all seem to hinge on people reading summaries of the book or hearing about it from someone else, so I strongly, strongly encourage you to read the entire thing and understand all the specific points in their respective context. It's not the book I was expecting to read based on the criticisms I'd heard.

To summarize the most common complaints:

1) Diamond barely mentions climate change at all, so I can only assume critics who accuse him of pushing a climate change "agenda" haven't really read the book very closely.

2) Diamond doesn't push environmental determinism, or generally claim that environmental conditions alone determine the rise and fall of societies. The multiple chapters dedicated to the Greenland experience of the Norse and the Inuit, who shared an environment but experienced different outcomes, is the clearest example that he is interested in the impact of culture and human agency on outcomes.

3) Diamond's thesis does not rest on his claim that the Greenland Norse didn't eat fish, despite this being a remarkably common criticism. The fish thing is an area where Diamond indeed may have been either outright wrong or at least oversimplifying the data. Luckily, there are so many other features of the Greenland Norse and Inuit experience he describes that I don't think removing the fish claim entirely would change the fundamental point much.

4) Diamond doesn't claim that the inhabitants of Rapa Nui (Easter Island) were stupid or self-destructive - his key thesis is that Rapa Nui's environmental conditions were different to those of other Pacific islands in ways that challenged socioeconomic models of Polynesian society that were sustainable on other Pacific islands. He also references a number of archaeological findings that his critics claim he ignored (such as changes in midden contents relating to diet, and rat-chewed palm nuts). The main issue I've seen with that chapter is that he doesn't dive into evidence for the island's population being higher in the past - but I have yet to find any critics providing evidence that the island's population has been stable, so that whole question seems like a wash, unfortunately.

To in short - it's not a climate change screed, it's not a Europe-hating manifesto for technological primitivism, it's not a colonial white supremacy pamphlet, and it's not a case for environmental determinism.

It's an exploration of the ways in which soil quality, water salinity, wind currents, biological resources, and topography pose challenges to human societies, or provide opportunity for them to flourish. It's an imperfect but interesting read that provides some much-needed perspective on our relationship to the material world around us, and I recommend closely reading it.