The Australian government released the business plan for NBN Co today which outlines the “cost-benefit” case for creating a monopoly wholesaler of fibre-based broadband services in Australia and investing some $A27 billion in public funds to create the network. The business case has been the focus of much political debate over the last year or so and as usual most of the debate has been conducted on a spurious basis – that is, the assumption is that the budget outlays proposed represent a “cost” to government and that by committing funds to this project the government is less able to “afford” other projects – presumably because there is some “budget balance outcome” that it cannot deviate from. Neither proposition is valid. While this blog has an Australian flavour the general economic principles apply to all national governments contemplating large-scale public infrastructure developments. The general point is that the provision of public infrastructure does not have to earn commercial returns.