We fear for the future of the nation if this is the level of public economic discourse:

Fiscal austerity has become such a staple of conventional wisdom in the UK that anyone in public life who challenges it is written off as a dangerous leftist. Jeremy Corbyn, the current favourite to become the next leader of Britain’s Labour party, is the latest victim of this chorus of disparagement. Some of his positions are untenable, but his remarks on economic policy are not foolish and they deserve proper scrutiny.

Corbyn has proposed two alternatives to the UK’s current policy of austerity: a national investment bank, to be capitalised by cancelling private-sector tax relief and subsidies;

Very well, let us take this seriously.

The £93 billion in "private sector tax relief and subsidies" that Corbyn is talking about is a number made up out of the aether by a sociologist from a third rate university. Farnsworth, for that is his name, has decided that depreciation allowances for companies investing in capital equipment are in fact equivalent to the taxpayer paying for that capital investment. And that is by far the largest component in that £93 billion.

That is, the suggestion is that we will get more investment by taxing investment more heavily. This is of course ludicrous, economic insanity of the highest order.

And here is where we get worried about the nation. Robert Skidelsky, that is, Baron Skidelsky, Emeritus Professor of Political Economy at Warwick, is describing this as something not foolish, something we should take seriously?

Shouldn't we worry about the future of the nation when the supposedly sensible, the adults in the room, get swept up in this sort of mania?