There’s a myth propagated by the far-right anti-EU brigade – that the “original” European Economic Community (there was an earlier ECSC) was only ever about a single market for goods and services. As can be seen from the Schuman Declaration, the long-term aim was always political integration :-
A united Europe was not achieved and we had war.
Europe will not be made all at once, or according to a single plan. It will be built through concrete achievements which first create a de facto solidarity. The coming together of the nations of Europe requires the elimination of the age-old opposition of France and Germany. Any action taken must in the first place concern these two countries.
Now you could argue that a unified Europe is undesirable and that it is perfectly reasonable to stop at a single market. That would be an agreeable position – stupid in my opinion, but valid.
But arguing that unification was never the goal would be dishonest.