Sam Bowman writes on the divide between boosters and doomsters - those who believe we can boost economic growth and those who don't. He misses, however, an important point.
This is that economic policy is not made by Sam, nor by Giles Wilkes, Stian Westlake, Aaron Batani or Torsten Bell. Policy-making (at least in the UK now) is not a meritocracy in which the people with the best ideas get the most say. Nor of course is it a democracy in which we all have equal say.
Instead, a mere glance at the Tory leadership contest (and a mere glance is all any of us can stand) tells us that policy is made not by the masses, nor by those of ability, but by those who can best appeal to a small minority who have little knowledge of economics and little desire for higher growth.
Given this, talking about what policies will raise growth is futile*. It begs the question: how can we create a polity in which sensible economic policy is even feasible?
The problem is that there are many structural barriers to growth-enhancing policies.
One was described by Joel Mokyr almost 30 years ago:
Sooner or later the forces of conservatism, the "if-it-ain't-broke-don't-fix-it," the "if-God-had-wanted-us-to-fly-he-would-have-given-us-wings," and the "not-invented-here-so-it-can't-possibly-work" people take over and manage through a variety of legal and institutional channels to slow down and if possible stop technological creativity altogether.
These forces of conservatism block some policies that could boost growth. Landlords would oppose any measures to reduce house prices or to shift the tax base from incomes to land. Lawyers and accountants don't want tax simplification (one good benchmark for any Budget should be the question: how many accountants will it make redundant?) Nimbys oppose inrastructure spending, even if it is green. And incumbent companies oppose tougher competition policy, or even anything that fosters business start-ups.
I'd add that the financial sector generally is such a force of conservatism. it benefits from the low real interest rates that stagnation brings. Sure, General Motors favoured pro-growth policies in the 50s as it needed a mass market. But Goldman Sachs has much less need.
Pablo Torija Jimenez and Martin Gilens and Benjamin Page (pdf) have shown how policy is set with regard to the interests of the mega-rich. But many of these are opposed to the reforms necessary to boost growth.
Rentiers, though, aren't the only force of conservatism. Back in 2006 Ben Friedman showed that economic stagnation fuelled illiberalism, racism and reactionary politics. Subsequent events have proved him right. But this means there's another big constituency opposed to growth, and not just gobshite culture warriors such as Farage or GB News. Why should Tories trouble themselves with the tough thinking and difficult admin required to raise economic growth when they can win elections simply by promising to deport migrants?
Yet another such force, of course, is the media. And I don't mean only the mouthpieces of tax-dodgers, rentiers and racists. I'm thinking too of our most influential outlet, the BBC. As Simon Wren-Lewis has documented, it has for years thought of economic policy merely as being about "the nation's finances" with good policy being only about fiscal responsibility - which is of course oblivious to basic economics.
We heard an example of this error on the Today programme this morning, when the interviewer accepted Rachel Reeves' claim that nationalization was inconsistent with Labour's proposed fiscal rules thereby missing the big story - that Ms Reeves is unqualified to be Chancellor because she doesn't know the basics of double-entry book-keeping.
The media, though, is not the only barrier to sensible policy-making. So too are voters. A vote for a hard Brexit was a vote against economic growth. Sure you might think this was because voters were misinformed about its economic effects. But this only raises the question: if they ignored good economics on Brexit, what makes you think they'll accept good ideas to raise economic growth?
I fear there's another issue here - a form of what John Jost calls system justification (pdf). 15 years of stagnant incomes has merely led to resignation, adaptation and learned helplessness. Many voters think we just cannot have nice things, and that any party offering them is dealing in fantasy economics.
Of course, good economists are having the debate Sam describes, of whether policy can raise growth**. But this debate is like writing a menu when you don't yet have a kitchen nor even much hope of ever getting one. Before thinking about economic policy we must think about how to give sensible economics any political influence. Brains are not enough. What matters is power.
I confess to not having answers here. Part of the answer, though, I suspect is to build and support movements which offer countervailing power to the forces of conservatism - movements which tell politicians that there are costs to them of kowtowing to rentiers and reactionaries. This is why some of us welcomed the mass politics inspired by Corbyn - but also, of course, why that met with swift repression.
* Well, maybe not entirely. Such talk could be a transitional demand - a way of saying "here's what you could have if our system wasn't so dysfunctional", and thus a way of raising discontent with the system.
** FWIW, I incline to the doomster camp but believe that many potentially growth-boosting policies (tax reform, better immigration policy, competition policy, better vocational training) are free hits: even if they don't boost growth much, they'll not hurt it either.