The Anglosphere is united through history, culture, common law, language and the same sovereign. More practically, our countries are all extremely high English speaking (Canada the lowest at 60%, and the UK the highest at 90%), we saw similar unemployment rates, GDP, and qualities of life making unification all the more plausible.
More info on this here: http://www.canzukinternational.com/why-canzuk
What we seek is
1) Free trade between the UK, Canada, Australia and New Zealand.
2) Freedom of movement between all Anglo nations & right of settlement for Anglos in non-Anglo countries
3) Elevation on the status of the monarch, and promoting the Monarchs role as rightful head of the Anglosphere
4) Anglo heritage should be celebrated and promoted.