Now Malcolm's sucked in. Hot on the heels of his predecessor, who labelled the China-Australia Free Trade agreement an "export agreement" (when his own modelling showed it would boost imports more than exports), and claimed it would create hundreds of thousands of jobs (when his modelling said it wouldn't even create tens of thousands), Turnbull says the 12-nation Trans-Pacific Partnership will be a "gigantic foundation stone" for Australia's future.

Pressed by an eager Neil Mitchell on Radio 3AW last week for details about the jobs it would create, he said: "More jobs, absolutely. Australian jobs depend upon open markets and free trade".

Which is a pity, because the only economic modelling we have shows it won't create jobs. It'll boost the Australian economy (slightly) by shifting workers away from some jobs towards others, but it will replace rather than add jobs, in the same way as things that are modelled usually do.

Our own Productivity Commission is itching to model the effects of the Trans-Pacific Partnership. It's the sort of task it was set up to do. But for some reason governments don't ask it to, so in this case we have to rely on the work of the prestigious Peterson Institute for International Economics in the United States. It is a supporter of the TPP. One of its blog posts is called "The Case for TPP". Another is titled: "A Convincing Case for Passing the TPP". Yet it finds the economic benefits are slight.