We're talking non nuclear?
US would win pretty handily by itself do to FAR superior naval forces. It has like twice the Aircraft carriers a combined europe would have, let alone other naval forces.
European forces really never get a chance to land on US Soil.
Including Nuclear? Who knows, it's a gambit.
Only real chance for the EU would be if it was a surprise attack by the EU on the US and they took over the US bases in Europe with their equipment.
As for economic factors... you'd expect Europe to have an advantage. But the whole Europeon Union barely equals the US, and Mexico and Canada outpace Russia and the non Europeon states. So North America actualy ends up with a war matieral, technological, economic and expierence advantage.
Really this just shows how absurdly overkill the US Army is.
