Here’s one piece of the story that I’d like to add in I-should-be-doing-something-else slapdash fashion: the New Deal, WWII, and the Marshall Plan sucked in curious, ambitious academics like Schelling, Galbraith, (Strangelove!) etc., and they accrued lots of responsibility, prestige, and data. They demonstrated disciplinary flexibility, and their work proved applicable to international conflict, so once the Cold War set in, they were the go-to civilians for the national security state.
So if I’m right (and I’m certainly out of my depth here), it’s an accident of history that elevated economists to their status as cross-disciplinary policy experts. If similar conditions to WWII or the Cold War were to emerge tomorrow, we might instead cultivate a cadre of evo-psych experts or cognitive scientists and install them at the center of all our policy questions.
This topic leads to some pretty fun and important questions. Is there one intellectual/professional/academic discipline that is especially suited to synoptic, integrated thinking, or is that just built in to intelligence? Would we be any better off with, say, lawyers running everything? Was Paul Krugman right that becoming an economist was the closest thing to being a psychohistorian? Should a young Asimov reader choose a different line of work?