The debate is not about immigration and its benefits. We all believe in them -- Australia is a migrant nation. The debate is not about multiculturalism and it's not about the source of migrants. The debate is about whether immigration should be running at very high levels. It’s about whether we end up with a population of 36 million in 2050 in contrast to the previous expectation of 28.5 million. There are strong economic arguments against this immigration surge. Immigration worsens skills shortages. The tradesman who’s recruited for a specific job arrives with his family. Immigration adds more to the demand for labour than it contributes to the supply. The Productivity Commission Research Report (2005) The Economic Implications of an Ageing Australia made clear migration does not reverse the ageing of the population. Bob Birrell has pointed out you would have to run immigration at very high levels for a very long time to have the slightest effect on population aging. The population is aging in Australia and just about everywhere else. Get used to it. Nurture older workers instead of driving them out of the workforce the moment they turn 55. High immigration is not the solution. There have been very silly comments about immigration and infrastructure. I don’t know of any period in the nation’s history when people said that infrastructure had kept pace with population growth. It can’t. The worst gap was in the 1950s when the roads of new suburbs were unpaved and Gough Whitlam’s children had to travel from Cronulla to the city to go to high school and people had to wait years for a PMG-delivered telephone connection and Queensland was an education slum, etc. We will never see that level of under-servicing again. Federal and state governments struggle to keep pace. But struggle they always will. Increase the intake and the infrastructure gap will be more acute. South-east Queensland makes the point. In January one academic on the 7:30 Report said that we need a new federal authority to take responsibility for all planning. This, he declared, was the answer. Once we have it we can stick to high immigration. Really? As if shifting responsibility to another level of government would dispose of all the arguments over densities, sprawl, social equity, environmental assessment, design and sustainability. Actually Sydney, Melbourne and Adelaide (I don’t know enough to comment on Brisbane and Perth) already have very sound, environmentally sensitive metropolitan plans. Among other things they identify transport corridors and areas around rail stations or transport hubs as locations for higher density development. So they are public transport-based. They work to limit urban sprawl. Sydney has been most successful at this, achieving the highest percentage of dwellings in high and medium density. It has also got the highest percentage of the population using public transport. But our cities will be more congested with 36 million, no matter how much goes into public transport. The arguments over sprawl and higher densities will be more intense. There will be environmental loss and a loss in quality of life: the beaches choked, the adjacent national parks degraded by force of numbers, the congestion of peak hour more intense (there is no public transport system anywhere in the world that avoids peak hour congestion). The cities will work. They will be different cities and it would be a brave person who would promise they’d offer a better quality of life. Yet I’m far more worried about water -- that is, about Australia’s erratic rainfall as a constraint on the over-ambitious population growth we seem locked into. The business lobby won’t acknowledge any of this; they are focused on the total size of the economy, a crude measure. They don’t look at GDP growth per head. Increasing productivity is going to be harder, not easier, if this runaway immigration continues. And business should stop imagining it can have lower corporate tax rates and high immigration. High immigration mandates higher government outlays, and therefore higher taxation. You can’t add millions to the nation’s population and expect a lower tax regime. Public opinion has moved -- is moving -- and I don’t think the high growth option will be entertained politically, by either side.