Why a global currency should remain an impractical dream

A single global central bank would fail spectacularly, but this does not absolve policymakers of their responsibilities

Today's world is more economically and financially integrated than at any time since the latter half of the nineteenth century. But policymaking - particularly central banking - remains anachronistically national and parochial. Isn't it time to re-think the global monetary (non) system? In particular, wouldn't a single global central bank and a world currency make more sense than our confusing, inefficient, and outdated assemblage of national monetary policies and currencies?

Technology is now reaching the point where a common digital currency, enabled by near-universal mobile phone adoption, certainly makes this possible. And however farfetched a global currency may sound, recall that before the first world war, ditching the gold standard seemed equally implausible.