It is this concentration of income – at levels not seen since the 1920s – that is the real cause of the present crisis.
In the UK, the upward transfer of income from wage earners to business and the mega-wealthy amounts to the equivalent of 7% of the economy. UK wage-earners have around £100bn – roughly equivalent to the size of the nation's health budget – less in their pockets today than if the cake were shared as it was in the late 1970s.
In the US, the sum stands at £500bn. There a typical worker would be more than £3,000 better off if the distribution of output between wages and profits had been held at its 1979 level. In the UK, they would earn almost £2,000 more.
The effect of this consolidation of economic power is that the two most effective routes out of the crisis have been closed. First, consumer demand – the oxygen that makes economies work – has been choked off. Rich economies have lost billions of pounds of spending power. Secondly, the slump in demand might be less damaging if the winners from the process of upward redistribution – big business and the top 1% – were playing a more productive role in helping recovery. They are not.
Britain's richest 1,000 have accumulated fortunes that are collectively worth £250bn more than a decade ago. The biggest global corporations are also sitting on near-record levels of cash. In the UK, such corporate surpluses stand at over £60bn, around 5% of the size of the economy. This money could be used to kickstart growth. Yet it is mostly standing idle. The result is paralysis.
The economic orthodoxy of the past 30 years holds that a stiff dose of inequality brings more efficient and faster-growing economies. It was a theory that captured the New Labour leadership – as long as tackling poverty was made a priority, then the rich should be allowed to flourish.
So have the architects of market capitalism been proved right? The evidence says no. The wealth gap has soared, but without wider economic progress. Since 1980, UK growth and productivity rates have been a third lower and unemployment five times higher than in the postwar era of "regulated capitalism". The three post-1980 recessions have been deeper and longer than those of the 1950s and 1960s, culminating in the crisis of the last four years.
The main outcome of the post-1980 experiment has been an economy that is much more polarised and much more prone to crisis. History shows a clear link between inequality and instability. The two most damaging crises of the last century – the Great Depression of the 1930s and the Great Crash of 2008 – were both preceded by sharp rises in inequality.