> And the bigger your conclusion is (say, here is why/how Europe colonized the world) you'd better have a lot of evidence.
Sure, but I feel many academic historians have a bit of a double standard here. Did Foucault muster up mounds of evidence for his totalizing theories of power and social structure? Not really, he gestured at a few facts and then built an elaborate structure of theory on that very wobbly foundation. Yet he continues to be taken seriously in academia, whereas Diamond never has been.
I think that's partly because he was a "serious thinker" and Diamond is an "airport read," and also partly because theories like Focuault's are so flexible that it becomes a fun hammer you can apply to any nail ("social media is a panopticon!"), whereas Diamond's argument is specific to a particular historical arc, and partly because Foucault accords with the prejudices of the academy (there are hidden structures of power woven throughout society that oppress the weak) and Diamond doesn't (X determinism is bad, everything is "contingent.").