In 1901, the title of the British monarch on coins was changed to Brit Omn Rex (Britanniarum Omnium Rex ie King of all the Britains). In 1946, Winston Churchill envisaged the Western World as consisting of the United States of America, a United States of (Western) Europe (without the UK) and the British Commonwealth (the Britains). In other words, the British Empire was to develop into a worldwide confederation, with the monarch in London as Head of State, Commonwealth Prime Ministers’ meetings as the Executive and the Judicial Committee of the Privy Council as appellate court. As colonies developed into self- governing dominions they would each join the confederation as other Britains.
This was advocated by the Imperial Federation League between 1884 and 1914, supported by Joseph Chamberlain, the Colonial Secretary. There was an Imperial Prime Ministers’ Conference in 1897 on the occasion of Queen Victoria’s Diamond Jubilee. Chamberlain asked the assembled premiers to agree to imperial federation. The idea was vetoed by Sir Wilfrid Laurier, the Francophone Prime Minister of Canada. In 1901, Chamberlain tried to create the title (King of Greater Britain) for the new King/Emperor Edward VII. Again, this was stopped by Laurier. Therefore, Chamberlain abandoned the project. Instead, he could have and should have carried it out with the other self-governing colonies in Australia, Newfoundland, New Zealand and South Africa. The opportunity was missed because after the First World War, each Dominion (and the Indian Empire) insisted on separate international representation. Thereafter, nationalism took hold, culminating in the Statute of Westminster (1931) which granted independence to the Dominions.
It did not happen because the United Kingdom committed suicide by waging two life and death wars against Germany. In each case Britain declared war and could have avoided so doing. In the First World War, the United Kingdom lost half its national wealth. In the Second it was bankrupted and dependent on American loans (which were not finally paid off until the end of the century). As a result it lost the ability to police and sustain its empire. The Sterling Area had to be dissolved, and the colonies hastily granted independence. The British Commonwealth was renamed Commonwealth of Nations and abandoned any attempt to have common foreign and trade policies. In spite of this, sixteen Commonwealth countries retained the British Monarchy in 2000, showing that worldwide confederation would have been possible if the United Kingdom had retained the power and wealth to be its engine.