Thus far in the twentieth century Canadian statesmen have been faced with two major constitutional problems, one relating to external autonomy, the other to internal economy. The first of these was the adaptation of existing governmental procedures in such fashion as to make Dominion nationhood a political reality by institutionalizing the processes appropriate to what is now called “Dominion Status.” The second has been the development of a more closely integrated national economy within the framework of a federal system. It is not necessary to consider the advisability or soundness of pursuing either of these purposes; it is enough for the student of constitutional machinery that they have been widely assumed as desirable ends, pursuit of which is considered to be progress. The very fact, however, that the attainment of these aims has had to be sought consciously in the past twenty-five years, more than half a century after the establishment of the Dominion, indicates that they were hardly in contemplation in 1867. And, as there can be no progress without change, it must be recognized that the progressive fulfilment of Dominion national aspirations, externally and internally, must carry with it very considerable if not almost revolutionary alteration in Canadian constitutionalism.
The obvious purpose of the formulation of the principles of Dominion status was to place each of the Dominions on terms of constitutional equality with Great Britain. If each Dominion had inherited British institutions in their pure form, the result would have been the creation of half a dozen reproductions of the British constitutional system. But no Dominion was actually a simple replica of the British polity, and in consequence the declaration of the new status created almost as many problems as it solved. With regard to the external aspects, the Dominions differed among themselves as to the immediate desirability of the legal consequences of the new status, so the Statute of Westminster, 1931, was drawn in such a way as to apply automatically only to Canada, the Irish Free State, and South Africa; for the other Dominions, the Statute was to come into operation only when adopted by them. So, also, with regard to the internal aspects, special reservations were made in the Statute to protect the constitutional systems of Canada, Australia, and New Zealand from change.