No prime minister has been better equipped to do something about the state of our cities than Malcolm Turnbull. He turned down the use of a government-provided car in his electorate because he preferred to take the bus or ferry or, on some occasions, to walk the three or so kilometres into the city of Sydney. He caught a Melbourne tram on the way to the launch of his cities policy on Friday.

And in opposition he never had any time for Labor's rhetoric about how the National Broadband Network would make central business districts less important. Labor said Australians were going to work from home. Suburbs, small towns and the outback would come to rival cities as the places where things were done.

He mocked the idea again on Friday: "When the internet arrived 20 plus years ago, a lot of people said this will be the death of cities. People won't want to go into the city any more, everyone will stay spread out, telecommuting, working online; people will be on an island or in a remote mountain site somewhere, a mountaintop somewhere.

"But what it has done is actually made cities and centres, whether they are big cities like Melbourne or regional centres, it's made them more important. By our nature, we are social animals. We are at our most productive, our most creative, our most innovative when we are together. That's why an efficient city, a liveable city, is absolutely critical to the growth, of our economy."

But what he has proposed in a padded-out 35-page smart cities plan is almost entirely lacking in specifics. Yes, it's a good idea to leverage the balance sheet of the Commonwealth to build the roads and other facilities that will make cities work. But as to mechanics, that'll be the subject of a summit. Then he'll spend $50 million setting up a team to work out what to do. What he won't be doing - right now, when it would show up in next Tuesday's budget - is borrowing cheaply to set aside big licks of money that will be needed. He says it will happen later.

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