That high-pitched whining noise is coming from Canberra, where miners are calling on the Australian government to reverse its proposed super tax on resource profits. The campaign is urging that the new rate be applied to new projects only, and to reduce that rate from 40 per cent.

On both, the miners have a decent case. The proposed tax applies to all operating earnings on Australian projects, deductible against company tax with concessions on capex, exploration and development. That would have an outsized impact on companies harvesting cash from a heavily depreciated asset base, such as Rio Tinto or BHP Billiton, with decades of investment in the Pilbara. Lifting the effective taxation rate from about 40 per cent to 55, meanwhile, would give Australia one of the world's harshest fiscal regimes, 14 per cent above average.

Basic game theory, however, suggests the industry will win one concession but not both. The Australian government will have been encouraged by appreciative noises from Chile and Brazil; Congo, Zambia and Mongolia are also likely to follow suit, says UBS.