In modern world large economies have advantages (bargaining power, unified standards, and many more) and this is one of the main reasons why EU has been created.

Now when Britain is leaving the EU why no one thinks about building a union of UK, Canada, Australia and NZ, with free market and free movement (so Commonwealth is not what I am talking about)?

They have similar living standards and culture, same language and even monarchy. Free movement in this union is much less likely to annoy Gillian Duffy as migrants will speak same language, share same values and most importantly work for same wages. What stops this process?

  • I could put forward 4 or 5 reasons, but since AFAIK there has been no proposal seriously debated by the public, so all I could give would be highly opinable. And while the nature of this site makes its answers more "open" than the sites about maths or programming, I think the question is way too much opinion-based (maybe in worldbuilding.stackexchange.com, if properly expressed? "I am designing a world where people from UK, NZ, Aus and Can want to form an union, but I want to think of forces or people who would realistically opposse that") – SJuan76 Oct 27 '16 at 15:50
  • Anyway, I can't resist quoting George Bernard Shaw: 'England and America are two countries divided by a common language' (not that any of my guesses are in that line). – SJuan76 Oct 27 '16 at 15:52
  • I voted to close as opinion-based for a different reason. Explaining why something didn't happen is impossible unless we have a near-total understanding of the subject. We could answer a question about why countries adopt free-movement policies, but we can really only speculate why something doesn't happen. – indigochild Oct 27 '16 at 17:14
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    For starters, they don't share any borders...which (IIRC) was one of the key reasons for the initial EU. – user1530 Oct 27 '16 at 19:44
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    Lack of shared borders was not an issue 150 years ago. Why would it now? – Need to know Oct 28 '16 at 9:41