Thanks for posting this +Sam Harris
. Really enjoyed Pinker's polite disarming of Kaplan's unscientific Realist arguments.
Realist IR has never had sound footing, yet it continues to be the dominant mode of thinking behind international tensions. See for example the quietly growing tensions between US and China, and the military buildup and positioning by both sides in the Pacific. Hillary Clinton recently even openly stated at a Pacific nations meeting that their agenda was based in "realpolitik". Awkward.
During the parts where Kaplan wasn't entertaining himself with his Realist fantasy, I think the substance of the talk came out as the recognition of the tangible benefits from institution building over the past century. It seems we can, with some degree of statistical certainty, credit the past century's progress towards peace to democracy and liberal internationalism.
Though I think the bigger story going forward may well be the benefits to be reaped from Feminist IR. Which ironically, Kaplan did mention.