The ethical and professional issues involved in urban design for military repression are clear. But the usual civilian applications in rich cities in the Global North (most often tech hubs themselves) are, leaving aside issues of privacy and governance, at best tangential to the major urban problems of the century.

Hundreds of millions of of us, certainly the most vulnerable, will be refugees escaping mutually reinforcing crisis of ecological collapse and violence. And unless present economic trends change, hundreds of millions more will live in hollowed out economies with staggeringly exponential levels of inequality. They won't live with configurable sidewalks and smart buildings; going by present practice (and Pentagon planning documents) surveillance by armed drones and collapsing or missing basic services — depending on whether you live in a broken society or are trapped in transit trying to escape one — are much more likely to be the case. We have developed a single mode of advanced high-information urbanism both for military and for civilian use, one focused on the dual models of targeted advertising and targeted violence.

Needless to say, it's not a model that helps with the underlying problem of a refugee camp or a hollowing out town or neighborhood: neither is ecologically nor economically self-sustainable. The sort of high-tech urban intervention most common today boils down to surveillance and control, which in fact worsens the problem. Even well-meaning, ingenious technical solutions to help with short problems of logistics, health, and so on, are stopgaps, saving lives but only for as long as the budget lasts, which is more or less until a worse emergency occurs somewhere else.

The root of the problem is that, whatever we know of how cities are born, survive, and grow, we don't have a repeatable kit of instructions to create or heal them quickly and cheaply enough. Urban renewal is a dicey prospect even in decayed formerly advanced cities; turning a refugee camp or shelled-out city into a vibrant economy is a much harder one. And on this problem, the urban policy problem of the century, technologists have done very little. There's money and prestige in upgrading the already advanced infrastructure of the high-tech cities where most technologists live, and there's at least money in the development of surveillance and (eventually violent) control technologies that are deployed, with different casings, both in rich cities and in the ubiquitous non-wars we're all not-fighting.

We are getting very good at building well-surveilled cyborgs out of rich cities and occupied zones, but we don't know how to use those technologies to help cities heal socially and economically or even build new ones from scratch. The difficult parts aren't technical, and in fact intersect with deeper issues of policy and politics: countries with failing infrastructure in major cities don't seem likely to invest in building new ones for displaced people, even internal migrants.

Bruce Sterling famously said The Future is About Old People, in Big Cities, Afraid of the Sky. The only thing to add to this is that those cities are most likely to be broken, either because of chronic underinvestment, or just plain old drone bombings, IEDs, or tanks. Or perhaps because the city consists of thousands of tents in a no-man's land between a place they were bombed out of and a place they are not allowed into.

They will need those cities to work. Cheaply, quickly, and well. Sustainably, economically and ecologically, for the long run.

That's the biggest urban technology problem of the century, and soon it'll be the most urgent one.