World War II and its immediate aftermath dominated the 1940s. Thinking of air raid precautions, volunteer defence corps, married women adding factory work to domestic duties and families worried about their loved ones overseas, Tasmania's experience of this conflict was not unique, although it was again shaped by geographical location if in ways very different from, for example, that of the Northern Territory. Thus Tasmania promoted itself, and came to be seen by the war planners, as a safe place to produce ammunition, boats, equipment and food. Even so, in 1940, the year which saw Tasmanian soldiers leave for the North African campaign with the Australian 6th Division, German naval raiders laid mines off Hobart. Indeed, Bass Strait was closed when mines actually caused the loss of a British steamer. Then in 1942, even beyond 42° south, there was a reminder of the other enemy when a Japanese submarinelaunched seaplane made a reconnaissance of Hobart.
On the home front, new Tasmanian-based Commonwealth agencies carry the story, although as explained in Chapter 2 the Australian Aluminium Production Commission (CA 250), established middecade and based in Sydney, should not be overlooked. The defence chiefs reorganised, resulting in, for example, Naval Staff Office, HMAS Cerberus VI (CA 1548), and Headquarters, Tasmanian Lines of Communication Area, Australian Military Forces (CA 1575). In their different ways, agencies like the Security Service, Tasmania (CA 748) established in 1941, Tasmanian War Industries Committee (CA 476) in 1942, Deputy Director of Reconstruction, Tasmania (CA 3469) in 1945, Department of Immigration, Tasmanian Branch (CA 960) in 1946, War Service Homes Division, Tasmania (CA 1625) in 1947 and ASIO Tasmania (CA 1560) in 1949 were also significant markers of the Commonwealth's role and a changing society. Renewed immigration needed the most adjustment and attention from the record-creating officials when in 1947 migrants of mostly Polish and Dutch origin began arriving to work for enterprises such as the Hydro-Electric Commission (HEC) and Electrolytic Zinc Works.
In the 1940s – if one had to nominate a decade – the Commonwealth came of age. Its powers were not as pervasive as John Curtin and Ben Chifley, the decade's two dominant prime ministers, would have liked yet, because of factors such as uniform taxation, support for higher education and an expansive take on post-war reconstruction, the balance of shared powers shifted irrevocably away from Hobart (and other capitals) in Canberra's favour. Watching his state's interests as Premier for almost the entire decade was another consummate ALP Catholic trade union moderate, Robert Cosgrove. The name Lyons re-appeared too when Joe Lyons' widow Enid, was elected Member for Darwin in 1943 (then unheard of in the House of Representatives). Dame Enid went on to enjoy a second first in 1949 as Vice President of the Executive and thus a member of the new Menzies Cabinet.