Since you bring it up: the US is a $18-trillion economy. Europe is a $19-trillion economy, of which about $18 trillion is from states in the EU. In that respect

Since you bring it up: the US is a $18-trillion economy. Europe is a $19-trillion economy, of which about $18 trillion is from states in the EU. In that respect, it's the only comparison that makes sense. (Well, maybe that and something like the UK and Germany vs California and Texas, roughly $3T vs $2T each).