Saying the entity "EU" is a single economy but the entity "US and China" isn't seems rather arbitrary to me. At the very least, euro is already a currency disco

Saying the entity "EU" is a single economy but the entity "US and China" isn't seems rather arbitrary to me. At the very least, euro is already a currency disconnected from a single economy, being currently connected to at least two: the relatively sane part of eurozone, and PI(B)IGS.