Faustian pacts are not a good idea. On assuming office in 2010 the coalition entered into a pact with the Bank of England and the financial markets which ranks as one of the most ill-conceived ventures in economic policy by any British government since the second world war.

It was to be deficit reduction – indeed the elimination of the so-called “structural” deficit – by 2015, in return for supportive monetary (including exchange rate) policy from the Bank of England and the enthusiastic backing of the financial markets. The sine qua non as the criterion for success of this policy and pact was to be a marked improvement in the pace of economic recovery.

The chancellor, George Osborne, made a bad start by raising VAT – a £12bn blow to consumer spending, with additional multiplier effects. The economy the incoming government inherited was recovering, albeit slowly. But the combination of the perverse increase in taxation (knocking almost 1% off gross domestic product per annum), and the impact of the austerity programme was sufficient to stop the recovery in its tracks.

This added to the deflationary impact of higher import prices arising from the massive – but necessary – devaluation of the pound in which the Treasury and the Bank of England had acquiesced. Then there have been all the other depressing influences on real incomes of which the governor, Sir Mervyn King, recently complained.

I should emphasise that paradoxically, an increase in energy prices can be inflationary in that it affects the general price level and deflationary in that, via the impact on real incomes, it has a depressing effect on spending power and therefore economic activity. Thus the monetary policy committee can be criticised by purists for not hitting the official inflation target of 2%, yet praised for not taking its brief too literally, and aggravating the depression.

For depression it is: in common with the redoubtable Jonathan Portes of the National Institute of Economic and Social Affairs I have regarded the term depression appropriate to a situation where output continues to remain well below its previous peak, let alone the 15% or so by which it is below what the historical trend would indicate.

In a paper which I recommend to all (“How to Restore Growth and Cut the Deficit, The Policy Consequences of Revived Keynesianism, Lombard Street Research“) the economist Christopher Smallwood reminds us of Keynes’s definition of depression: “a chronic condition of subnormal activity without any marked tendency either towards recovery or towards complete collapse”.

Although things are pretty bad, we have certainly avoided complete collapse – so far! The role of Gordon Brown and others in “saving the world” in 2008-09 was vital in preventing disaster then. Central bankers since had either read or heard about Liaquat Ahamed’s book Lords of Finance about how their predecessors got it so wrong in the 1920s and 1930s. Through quantitative easing – open market operations to offset a private sector credit crunch by easing monetary conditions – the central banks have stopped the rot.

Quantitative easing was urged way back by Keynes in order to lower interest rates. But it was when monetary policy was ineffective – like “pushing on a string” – that Keynes advocated what have come to be known as “Keynesian” policies – the use of fiscal policy (government spending) – to revive activity.

Unfortunately, under the Faustian pact we have witnessed a double whammy: fiscal policy being used to reduce government spending when the economy is already depressed. And a monetary policy that has been pushing on a string.

As Smallwood points out, the Treasury and Bank drew the wrong conclusion from the apparent success of the combination of fiscal contraction and monetary expansion in the 1980s and 1990s. “In both cases, the contractionary impact of tax rises and spending cuts was counterbalanced by substantial falls in interest rates, and of the sterling exchange rate at a time when our export markets were growing,” he writes. Exports and investment took up the slack left by budgetary cuts.

This time there was not much further for interest rates to fall. Indeed, banks were widening their margins and many borrowers did not feel the intended effects. For some, interest rates actually rose. Moreover, despite the more competitive pound, the sluggishness of our main markets prevented an export boom.

George Osborne cannot bear to admit he has been wrong, blames the Bank, and produces a Canadian ex machina in the shape of Mark Carney. And so far from pleasing the financial markets with this austerity programme, he finds they are more concerned about lack of growth, or continuing depression. Indeed the markets showed signs of incipient panic when they learned last week that King himself wanted more quantitative easing at the last meeting of the MPC.

Now, following recent work on the operation of “fiscal multipliers” in the US, Smallwood argues that a switch to a policy of fiscal expansion is the only way out. The multiplier was a discovery of the economist Richard Kahn’s, which Keynes adopted. Normally economists think of additional public spending or tax cuts having “multiplier” effects, as the person or institution in receipt of extra funds spends them in a way that boosts the incomes and spending of others. Similarly, higher investment produces what economists call “accelerator effects”.

But at present we have very damaging negative multiplier effects, in which budget cuts lead to obvious hardship, to further reductions in people’s ready cash and consequent social problems.

Smallwood argues convincingly that fiscal policy needs, selectively, to be put into reverse. “A properly designed fiscal stimulus could restore growth, at the same time generating powerful tax flow-backs from (a) national income (multiplier effects); (b) higher private investment (accelerator effects); and (c) improved long-term growth potential as a result of increased investment.”

There is a huge range of potential infrastructure projects out there. They can pay for themselves. The only way out of this mess is a complete reversal of fiscal policy. It would be seriously ironic if the financial markets ended up punishing this country for the unintended consequences of a Faustian pact that was meant to please them. The ratings agencies have already started.