We are entering an era of massive population transfer - a rural exodus of unprecedented proportions. In Asia and Africa farmers and peasants are being lured to mega-cities. This brings myriad benefits in terms of transport and energy use, but it also brings new forms of risk.
Shenzhen in China and Lagos in Nigeria are swelling to gargantuan size. But even a city as large as Shenzhen is easily swallowed by the megalopolis now forming between Macau, Guangzhou and Hong Kong. A UN Habitat report from 2010 estimated over 120 million people living in this region alone. This enormous population pressure can be dangerous.
Two events expose these risks; the SARS outbreak in 2002 and the recent earthquake and tsunami in Japan.
As population centres creep closer to rural areas and expand around fault lines or flood zones, the death toll from traumatic events can rise exponentially.
The catastrophe in Japan could have been significantly worse, had it not been for some important measures; such as a sophisticated tsunami warning system and a strict building code.
Though we like to think the reason for a low death toll during the recent floods and cyclones in Australia had something to do with our plucky national character or Queensland Premier Anna Bligh’s political virtuosity, these had very little real impact. The death toll was low because very few people live here.
Australia is the second most sparsely populated continent on earth – more populated than Antarctica and one fifth as dense as South America.
On the other hand, countries with high population densities and without the benefits of first world membership such as Haiti or Bangladesh are savaged by natural disasters in even more catastrophic ways. The combination of urban density, poor infrastructure, poor governance and poverty is deadly.
The death toll from the 7.0 magnitude quake in Haiti last year now stands at a staggering 300,000. The tragic but eventual intersection of urbanization, natural disaster and epidemic will cause these figures to balloon further.
The strategic challenges facing city-making are significant.
Do we abandon the poor to live in high-risk areas? How do we support industrial growth and urbanization in developing countries? What about migrant workers and refugees – do we open our cities to them or close the gates behind us?
These are not abstract questions, it is a calculus for deciding who gets to live and die.
Consider climate change. Can we even use the term natural disaster to describe events that might be man-made? During the 2009 Copenhagen Summit, the Group of 77 developing nations despaired at the deal being offered them.
In order to protect their status as carbon emitters, China, the United States Australia and other developed countries were pressing for an end to Kyoto and the acceptance of a two-degree temperature increase.
As the Sudanese negotiator Lumumba Di-Aping made clear, this temperature increase would turn Africa into a furnace, condemning millions to death from starvation and water stress.
The calculus works like this; carbon capacity on earth is limited, so countries will fight to protect access to it, they do so because it directly relates to industrial output.
But what happens when our industrial output affects temperatures in Africa, resulting in mass migration, including to Australia? How do we assess our responsibilities in this situation? How do we disentangle our immediate interests from their distant effects?
The problem is knotted. Climate change and the urban traumas that can ensue radically change both the distribution of and responsibility for risk.
When the fate of someone in New Orleans becomes linked to the fate of a slum dweller in Bangladesh or a resident in Ipswich, just because the banks of the Mississippi delta, the Indian Ocean or the Brisbane River threaten to flood, a new network of shared risks is formed.
These networks have the power to tie distant fates together, transforming existing networks based in nationality or ethnicity.
The problem of urban trauma brings these difficult political questions into sharp focus. Studying these moments of breakdown is difficult but revealing.
When cities go wrong, they often expose things that normally remain hidden, such as when Hurricane Katrina laid bare the severe economic inequalities of the United States.
In Australia, the long cycles of environmental trauma; fire, drought and flood do not synchronize with the electoral cycles.
We need much better quality long-term strategic thinking rather than short-term political expediency. Maybe we need to make an electoral cycle the same length as El Nino?
There is no doubt that certain parts of the world, Australia included, will at some time in the next century become increasingly unviable for settlement due to climate change.
Though the situation in New Orleans and the situation in Brisbane could not be more different, they both expose the inevitability of having to make very difficult political decisions on settlement.
Do we continue to build and repair homes built on flood plains? Do we change the building typology to something more suitable? Do we slowly relocate people to higher ground?
These questions now face Japan, both with regards to future tsunamis and nuclear energy generation.
Are these extreme densities in areas of high-risk viable in the longer term? How do neighbouring countries ensure that clouds of radioactive particles will not blow over the border after a meltdown?
Because populations are expanding rapidly, it will always be easier to address these issues now rather than later.
Asking how and why we make our cities is a question of great importance to everyone. It goes beyond lifestyle and leisure; it is about prosperity, access, equity and risk; how much wealth can we produce in common, who is included within the city, how do we share its resources, how do we share responsibility for the risks it produces?
In this regard, Sydney can assume a strategic role in the region. What we need in this city first, is a broad and high-level debate about the city that can move beyond the inconsequential local trench war about what can be developed in the area of Bangaroo.
It is time to look over the backyard fence, there are much bigger issues at play.