Could any navy realistically surpass Britain before the mid-twentieth century?
Short answerOnly the United States had comparable industrial capacity, and it was unlikely to fund a decisive naval build-up without a major war.
NotesBefore 1955, Britain retained the industrial base to expand its fleet if it considered maritime supremacy necessary. The United States was the only plausible challenger, but Congress would usually require a major war before funding the scale of construction needed to surpass Britain. Treaty limits could therefore suit both sides by making naval status affordable to defend politically. The comparison is about mobilizing shipyards, finance, and imperial or continental resources, not merely counting the fleets already in commission.