The British state can well afford to spend whatever it takes to cover lost wages, keep companies afloat, and hold the economy together through the Covid-19 crisis. There is no debt constraint. Nor is there any coherent alternative.

Rishi Sunak has taken exactly the right steps in covering 80pc of wages - up to £2,500 a month - for staff kept on by companies but unable to work, and to offer the self-employed access to Universal Credit at rates equal to statutory sick pay.

It prevents wholesale destruction of our economic base. It greatly raíses the chances of averting a protracted slump, or worse yet, a deflationary depression. It is executive action befitting the war-time threat that we face.

Some cavil at the cost. They are wrong. To deny funding on the basis of primitive accounting shibboleths would be to repeat the errors of post-Lehman austerity strategy but on a greater scale, and with more calamitous effects.

In that episode, public investment was cut to the bone – even though we could borrow at negative real rates – and this pulled down the rate of future economic growth for a decade. It was based on the false theory of “expansionary fiscal contractions”, debunked by the International Monetary Fund, and the nearest thing to witchcraft in modern economic debate.