In the 19th century, after the Napoleonic wars, Britain distanced itself from European affairs to focus on its empire, which was the largest empire in the world, comprising roughly 25 per cent of the world. However, in the 20th century, Great Britain fought two wars in Europe and decolonized, losing most of its empire worldwide. The country also saw a decline in relative power and influence within the international system, with the U.S. taking its place as a world power. The days of Pax Britannica might be over, but Brexit became the latest British movement away from European affairs, with Britain officially leaving the European Union on December 31, 2020.

This movement towards a bigger international role in world affairs had Britain looking back to its former colonies for support and alliances, especially its former dominions such as Australia, Canada, and New Zealand. This was in anticipation that Britain might be dominated by the larger European Union. Even though Britain just spent five years negotiating a deal to leave the EU—where one of the largest concerns was over fishing rights, which contributes to less than 0.1 per cent of its GDP—it might spend the next five negotiating the creation of a new union, CANZUK.

The core differences between CANZUK and the EU, which might be the reason why some Eurosceptics support the creation of this new union, are that the cultures of all four CANZUK countries are extremely similar and they share the same language, two factors that often hamper negotiations within the EU.

Furthermore, the CANZUK union would also have stricter migration agreements, which would be similar to the already existent Trans-Tasman travel agreement between Australia and New Zealand, where travel between member countries is prohibited if the citizen has a criminal record, an infectious illness, or is considered a national risk.

Another fundamental difference between CANZUK and the EU is that the former would not have a supranational parliament, like the European Parliament in Brussels, which means that Australia, New Zealand, Canada, and the U.K. would keep their de facto sovereignty and have the independence to draft their own laws.

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Members of the CANZUK alliance would also keep the freedom to negotiate their own trade agreements with other nations, another core distinction from the EU, which requires all 27 member states to agree to any trade agreement. Consequently, Canada would be able to continue being a member of the North American Free Trade Agreement (NAFTA) and the Comprehensive Economic Trade Agreement (CETA).

Considering the world might be entering a new era of multipolarity—multiple superpowers—this union would benefit its four potential member states. Together they would have the economic, diplomatic, and maybe even military power to rival the EU and possibly even China and the U.S. Last year, Canada, the U.K., and Australia issued a joint statement criticizing the national security legislation China imposed on Hong Kong, with Britain and Canada also issuing a joint statement over the war in Nagorno-Karabakh.

The main issue concerning the logistics of the union is the large distances between CANZUK member countries, with Sydney being nearly 12.5 thousand kilometers away from Vancouver, and London being roughly 5.7 thousand kilometers from Toronto. Just within Canada, the distances between the east and west coasts are already large, with Toronto and Vancouver being nearly 3.3 thousand kilometers away from each other. The CANZUK union would entail longer distances than the 2.9 thousand kilometers distance between Athens and Dublin, two European capital cities located on the edges of the Union. 

Although some people might be skeptical of the CANZUK union, arguing that it is neo-imperialist behaviour from Britain, this union would undoubtedly be advantageous for all of its members. Not only would trade and movement of civilians increase between member states, but foreign policy cooperation would greatly improve as a result of having a union between those four nations. As mentioned before, Canada, Australia, the U.K., and New Zealand have already cooperated before in foreign policy, showing decisiveness and stepping up when there is a lack of decisive action from either the EU or the U.S. Ultimately, CANZUK would decrease the world’s dependency on support from the U.S. when dealing with foreign affairs like the Chinese expansion in the South China Sea or the Russian invasion of Crimea, and promote more peaceable trade and civilian relations between its member states.