It is precisely because we can change cities today (cleaner, cheaper, etc.) that their impact on our politics of land management must be thought again... From the origins !
Water was the main incentive for the first cities. Energy seems to be the one today (water still is, though). We've been through centuries of different experimentations in such matters. We have the technical means to do about anything...
So what do we really want ? Knowing that what's good for Croydon might create some problems in Aberdeen (Aah the lassies of Aberdeen!).

The French have coined a new territorial management law called the "Loi SRU" (Solidarité et Renouvellement Urbain) that for the first time includes not only sustainability, but also major risks (industrial, natural, etc.), and economical development.
It is quite a breakthrough... but it 's different parts are not followed by most mayors because it's seems to complicated... And because they have to rewrite the local rules !

This could be an European incentive, if we would allow some thoughts on our differences on such territorial management to find a common ground... (ground is the word :-) )

"What can I do, What can I write, Against the fall of Night". A.E. Housman