How much fiscal stimulus is too much? The debate on this question among economists who support the goals of Joe Biden’s US administration has become fierce. That is no bad thing: policy should be debated. In this crisis, as during the 2008 financial crisis, one has to evaluate the risks of doing too little against those of doing too much.

But one thing is clear: the fact that too little stimulus was delivered in 2009 does not mean that far more than that must be right today. Policy must be judged by its suitability in current circumstances while recognising the uncertainties and balance of risks.

I have no objection in principle to huge fiscal spending. Indeed, in January 2009, I argued that the US should run a fiscal deficit of 10 per cent of gross domestic product until the damaged balance sheets of the private sector were healed. Shortly thereafter, I argued that we had to learn from Japan if we were to understand the dangers then confronting western economies. I have also recognised from the start that a pandemic is an emergency, rather like a war. Policy did indeed need to go on a war footing.