The EC kept Franco-German rivalry down to the economic side and avoided war amongst competing powers for nearly 60 years. That IS an achievement
The fact that Poland and Germany and also Romany and hungary can work together is a major achievement
The Euro seems like a mistake yet it also opened up internal trade heavily.
There are lots of places where the EU is wrong, but throwing out the baby with the bathwater is the wrong move
I do not credit the EU in any form with that. That was more of the US involvement, especially when the Cold War was on. When the USSR broke up, things changed a lot.
The EU is based on the USSR. The governmental structures are USSR-based, just like the UN is (whose charter every EU treaty has declared “respect for the principles” thereof, and that charter is based on the 1936 USSR constitution just as Alger Hiss intended); the Commission acts as the Politburo as it both writes and passes laws, while the “Parliament” (which can’t write a single law) is its rubber stamp. It is not a good thing.
There is no baby in the bathwater. I’ve heard that aphorism from pro-EU anti-freedom types.
As far as “internal trade”, the EU actually does not facilitate that. It instead facilitates Germany’s manufacturing at the expense of the other member states. There would have been other ways to institute tariff-free trade, e.g. bilateral agreements. The EU also regulates things out of existence and encourages nationalization.