I think anything like EU-as-political-project is unlikely if the EU collapse, but for another reason. The EU is as a project to build a federal European state a project that tries to create and depends upon a European identity. And when those fail competing identities are strenghtened, which would be the member states as Neuro/Seuro identities are not developed. If the project returns in force it takes a generation or so.

So if EU fails I predict member states going their own ways with overlapping, weaker intergovernmental collaborations.

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