I like John Sanphillippo's perambulations around suburban USA. We spend too much time looking at big cities with their skyscrapers, trams or tube systems and air pollution. Suburbia is really important and undervalued by planners - it's true to say we probably need more of it.
Anyway Sanphillippo makes this telling observation about US land use:
After several years of traveling around the country in the presence of city planners, economic development officials, elected representatives, engineers, production home builders, professional consultants, and groups of concerned citizens I’ve come to my own personal unified theory of America’s land use future. The short version is that we’ve got the built environment that we have and the overwhelming majority of it isn’t ever going to change much. If you want to know what things will look like in thirty or forty years… look around. That’s pretty much it.Sanphillippo then goes on to observe that, for much of America, the big challenge will be looking after this infrastructure - roads, sewers, water supply - as much as it will be about new infrastructure. For Europe, with largely privatised utility suppliers there's less of a problem (if you want to see the case for a privatised water supply system look at the tragedy of Flint, Michigan) but we can see glimpses of the issue with the underinvestment in our road system. Indeed the contrast between the investment in maintaining rail systems and road systems is striking especially given the dominance of roads in transportation and their poor safety record compared to rail.
The public policy mistake is to focus on the excitement of new infrastructure like HS2 rather than on looking after the existing networks. Sanphillippo's point tells us this is the wrong approach and that we should be seeking to make more efficient use of exisitng systems for the very straightforward reason that those existing systems will make up 95% or more of any future system.
A final observation is that the coming transportation revolution - digital, driverless, drones and so forth - has to fit into the existing network as there isn't the time, capacity or cash to make the changes to public infrastructure. This is a challenge for those developing these new transport technologies and also a reason why places with less of those legacy systems such as Africa start the revolution with an advantage.