Some professors hold on to their careers for dear tenure, eking out threadbare research material and desperately placing articles in whichever journal will take them. When retirement comes, the waters of academia swallow them up so that they become barely a footnote on a conference paper. And then there are men like Paul Romer.

Romer is bulge-bracket academia, a departure-lounge economist: the kind of intellectual as likely to be found turning left on a plane as in seminar rooms. Forever mentioned as a future Nobel prizewinner, this Californian is a world expert on how and why economies grow. When Gordon Brown made that infamous speech about post-neoclassical endogenous growth theory, it wasn't Balls – as Heseltine jibed – but Romer he was quoting.

He's one of Time's "25 most influential Americans" (true, Time was the magazine that ran a joint profile of Cyndi Lauper and Madonna in 1985, and firmly declared that Cyndi was the bigger star, but that neither came "within a mile of Tina Turner's splendid album of racked soul, Private Dancer", but accolades such as these are still to be taken with due gravity of expression) . And then there are the adoring journalistic profiles, one of which began with the reporter turning up cap in hand to meet the academic lounging "poolside at his house, which overlooks a huge expanse of rolling ranchland". That, it perhaps won't surprise you to learn, was the hardest-hitting moment.

So Romer is a brilliant economist, and he has a new and big idea. And because he is The Great Romer, he gets to present this wheeze to national leaders, high-profile conferences and invitation-only gatherings of policy-makers. And because he has some spare cash (views over rolling ranchland don't come cheap, you know), Romer can afford to jack in his formal position at Stanford and start up his own think tank to make his case.

Trouble is, the idea stinks. With little track record in dealing with poor countries, Romer has come up a grand scheme for lifting Africa and Asia out of poverty. What they need to do, he argues, is give up a big chunk of their land to a rich country. Policy experts from Washington can take over a patch of Rwanda, and invite along GM and Microsoft and Gap to come and set up factories. Poor countries give up their sovereignty in return for the promise of greater prosperity.

His big example is Hong Kong. At the end of the first opium war in 1842, the Chinese were marched on board a British warship anchored off Nanjing and forced to sign Hong Kong away to Queen Victoria. Over the next 150 years, the little island turned into Asia's number one capitalist success story. It was an example that Deng Xiaoping ended up copying on the mainland, in coastal provinces such as Guangdong – to explosive economic effect.

China's loss of Hong Kong should not be seen as a national humiliation or great international injustice, Romer has written, but "an intervention" which has "done more to reduce world poverty than all the world's official aid programmes of the 20th century combined — and at a fraction of the cost". What the world needs, the economist argues, is not one but 100 Hong Kongs.

You think this is colonialism? For Romer, that "kind of emotion . . . can get in the way" (see what he did there? You have emotions; the elite economist has evidence). Sure, the poor people living and working in these new charter cities wouldn't necessarily have any democratic privileges such as the right to vote, but they could vote with their feet. And in the meantime, the Africans or the Asians would get the undoubted benefit of all this huge western expertise.

Romer's right, in a way. This idea isn't prompted by dreams of a new imperialism – because this California economist doesn't know enough imperial history. If he did, he'd realise that the English Whig Thomas Macaulay said it all before, when he said of India in 1833: "It is scarcely possible to calculate the benefits which we might derive from the diffusion of European civilisation among the vast population of the East . . . To trade with civilised men is infinitely more profitable than to govern savages." That was a view of the Empire as the white man's burden: then it came with Orientalists, now it is accompanied by corporate logos. In both cases it comes with great lashes of condescension and a lack of knowledge about the countries one is imposing on.

With a bit more history, Romer might acknowledge that mainland China had other areas that were so dominated by foreigners they too might be described as Charter Cities. Shanghai in the early 20th century had signs reading: No Dogs, No Chinese – and yet it didn't boom like Hong Kong did. He might also agree that there remains a big debate about how China has got so rich, with World Bank economists recently arguing that it is farming that has done most to reduce poverty, rather than industry.

One result of the great economic crisis is that academic practitioners are finally acknowledging that economic policy is not just a series of equations applied to the real world, but questions that ultimately have a political answer. Yet the old pseudo- scientific blank slate-ism still survives, as Paul Romer's latest project demonstrates.