Could a federal Commonwealth sustain a larger navy?

How could Britain have retained the empire into the millennium and maintained one of the world's largest navies?

The proposed route is a federal Commonwealth with self-governing states, shared foreign and naval policies, and pooled industrial capacity and infrastructure.

A federal or near-federal Commonwealth is proposed as a way to retain the combined power of several states. Shared foreign policy and a common naval policy would allow their industrial capacity and infrastructure to support a larger fleet. Local self-government would coexist with continued participation in a wider group. In this historical interpretation, the Commonwealth was a planned destination for much of the empire. Britain would remain the financial, political, industrial and research hub of the proposed group. Establishing that level of cooperation would be difficult, and describing the historical plans does not imply endorsing every feature of them.