Let's not overstate the case. The EU was built to keep France and Germany from getting into another war, and it has been successful at that. All the other "principles" are just window dressing.
Isn't it up to Europeans to define the purpose of the EU? What's your claim to having the right to define it?
I'm not defining anything. I'm just explaining why the key decision makers actually created the EU. The statements made for public consumption shouldn't be taken too seriously.
You're vastly underestimating the economic importance of EU integration.
Is that why the EU economic growth rate is so stagnant?
Simplistic reply without substance. The EU economic growth is influenced by much more than just the integration. It can be stagnant not because but despite the integration. It could also be the case that EU integration was an attempt to improve economy but it didn't work out.
So no evidence of economic importance.
Do you think it would harm the US economy if every state instituted its own currency, put up border checkpoints, only allowed its own citizens to work and live in-state, and imposed tariffs on all the other states?