For those who follow the stock exchange, building materials share values are the key to the boom and bust cycle of Australian (and similar systems) property, infrastructure and construction booms. When building materials values go down we know that overall market demand decline has settled in. It means that the developers and engineers have reduced their forward orders for bricks and mortar. At the same time Australian state governments have been told to reduce their own little-known immigrant-sponsorship programs.
Are business forecasts another key to Julia Gillard's apparent sea-change in population policy and Rudd's disappearance?
The ALP doesn't rely on mere donations from developers; it has its own huge investments in finance, insurance, mining, development and property, which act as a barometer for the benefits of growth. Could ALP investments and other big business now be warning the Labor Government that construction will no longer be able to soak up immigrants? Sure, pumping up population pumps up demand, but only if there is money to invest. Problem is that the money seems to be drying up.
Boral pulling up sticks
Building materials giant, Boral, long a veteran investor in Australian population growth and an early vocal member of the 20th century Australian population growth lobby, is downsizing some of its Australian and US operations and heading north, presumably scavenging the last inertias of scale in the post-colonial malignant growth of China, India and South East Asian regions.
The Australian Financial Review reported that Boral made a $49 million loss before interest and taxation in the first half of 2010.
The most tasteless era of ostentatious spending on multi-management layers wining and dining big projects and buyers since the one preceding the Great Depression may be on its last legs. The US housing market has gone phutt. The Australian market will follow.
And Boral shares, running at around $10 in 2006, are now about half that.
"Deutsche Bank believes that although Boral's Australian construction materials arm has been one of its strongest-performing divisions, with earnings before interest and taxation up 12 per cent to $107 million in the first half, it could easily cut some $14 million in costs by eliminating several layers of management." 
This will be a relief for less exalted workers and managers in the sector. Survival is possible in such industries if they follow the post 1970s oil-shock European model of maintaining infrastructure and housing stock instead of investing in population and construction growth. However, there won't be room for wedding-cake management tiers.
States told to cut their 'secret' immigration programs
Another sign of terminal decline in bricks and mortar bubbles is the new Federal Government's request to the states to cut back their semi-secret immigration programs, including the 176 visas. The states control land and derive income from its sale, notably through stamp duty. To generate land and housing sales they have been engineering population growth, in tandem with property developers and financiers. The associated state-sponsored immigration programs seem to have started in Victoria and are the most excessive there. Introduced by the Kennett government, one of their ploys was to make a low profile category of 'regional immigration' (once designed to assist low-population rural areas by facilitating skilled immigration and loosening definitions of family reunion) into one that applied everywhere, designating dense urban areas as in need of immigration. Long and short-term immigration in numbers previously unimagined has generated a demand for housing and jobs in construction. The same immigration probably supplies many of those non-English speaking construction-workers one sees moving like ants on roadways and tragically moon-scaped once green patches in Australian suburbs, carrying out orders at which most locals would bawk, if in control of the process.
State government spokespeople, including growth-corridor spruikers, have repeatedly claimed that immigration numbers were outside of their control, yet the states advertised aggressively for immigrants. See these articles, for instance: "Premier Bligh pretends Queenslanders cannot cap population growth although 60% want to" and "Melbourne 2008, Life in a destruction zone" and "Julianne Bell delivers resolutions to Planning Minister Madden in late impromptu meeting."
Yet the State Premiers continue to try to mislead the public on this, even subsequent to Gillard's new policies:
"We can't control who comes over our state borders, but the federal government can control who comes into Australia," (Anna Bligh) 
Tragically and wastefully the tendency of state governments to deny reality may see green wedges rezoned and destroyed even at this stage of construction detumescence by parliamentary rogues. See for instance, http://candobetter.org/node/2058 and http://candobetter.org/node/2067 Yet it may all be for nothing; those wedges might be sold at a financial loss in the end.
Women in power
We may gauge the panic of big business to the idea of a real debate on population through its mainstream media mouthpieces' hopeful perseveration with tying that rusty and irrelevant old racist can to the idea of sustainable population and Julia Gillard, reflected for instance, in this glowing chestnut where Gillard's red hair provides a cliched motif:
"Who can forget the last redhead to talk tough on immigration and protecting Australian values?
and "This isn't just about talking to voters in western Sydney but also in Queensland, which gave rise to Hansonism. Maintaining seats there is shaping as a major challenge in the federal election."
The comments above evoke the medieval European stigmatisation of red-heads, not to mention witch-hunting. Starting with the new Primeminister, women in Australia may be in for an interesting time as the boys start fighting over the scraps, in the property sector and government.
 Jeremy Wiggins, "Boral set to offload dead wood," Australian Financial Review, 28 June, 2010, page 1.
 Sophie Morris, "States' visas blunt skills thrust: Migration," Australian Financial Review, 28 June, 2010, page 8.
 Marcus Priest, "Values, being sustainable are the keys: Population,"Australian Financial Review, 28 June, 2010, page 8.
Marcus Priest, "Lurching to the right on boat people: Comment," Australian Financial Review, page 8.