How many people across the world in the history of humanity have fled from a capitalist country to a socialist one?

There was much amusement at the height of the long miners’ strike of 1984/85. A National Union of Mineworkers official from Yorkshire, a crony of Marxist trade unionist Arthur Scargill, sought sanctuary in the Stasi-controlled state of East Germany. He apparently felt unsafe under the jackboot of the Thatcher regime in the UK.

In the 1930s, some tens of thousands moved to Stalin’s Soviet Union, including the father of General Wojciech Jaruzelski, the leader of the last Communist government of Poland in the 1980s.

According to the euphemism used by the late Robert Maxwell in his biography of Jaruzelski, the father then “took a job in the north-east of the Soviet Union”. In other words, he was sent to the Siberian labour camps. He was lucky. Most of the other Poles who moved to the Soviet Union were subsequently shot.

These incidents stick in the mind precisely because they are so rare.

In contrast, when given the chance, millions flee from socialism. Venezuela is but the latest example. According to the United Nations, well over two million people have already escaped, taking with them just whatever they can carry.

The Berlin Wall was constructed in 1961 to prevent people moving from socialist East Germany to capitalist West Germany.

As post-war reconstruction got underway in the 1950s, around 3.5m left for a better life in the West – more than 10m translated into UK population terms. The Wall was built to keep them in.

The problem which the western countries have is not in keeping their own populations in. It is keeping others out, whether it is by Donald Trump’s wall in the US or Matteo Salvini’s refusal to allow boats of refugees to land in Italy.

The reason is simple. Economies based on market-oriented principles work much better than centrally planned ones. Capitalism, for all its faults, offers a much better lifestyle than socialism.

In the 1950s, South Korean living standards were not much better than those of sub-Saharan African countries. Now, South Korea is rich, while the North remains trapped in poverty. High-security levels are imposed by the latter to keep people in place. If they were removed, the country would rapidly become de-populated.

A fundamental concept in economic theory is that of revealed preference. People reveal what they really want not through answers to survey questions, but by their actions. If I say I prefer Pepsi to Coke but always buy Coke, I reveal that I actually prefer Coke.

Given the chance, over the years many millions of people have left socialist countries for capitalist ones. People were even willing to risk death to try to escape the old Soviet bloc countries.

By their actions, people reveal their preferences.

The financial crisis, scandals like Carillion, inequality and homelessness – all these are sticks for “useful idiots”, in Lenin’s phrase, to beat capitalism. But the point cannot be made often enough: whenever people are given the choice, they prefer capitalism to socialism.

Mark Carney, the governor of the Bank of England, hit the headlines at the weekend, claiming that Marxism could once again become a prominent political force in the west.

Automation, it seems, may not just destroy millions of jobs. For all except a privileged minority of high-tech workers, the collapse in the demand for labour could hold down living standards for decades. In such a climate, Communism may seem an attractive political option.

Karl Marx as an economist is a bit of a curate’s egg, good in parts. In the late eighteenth and early nineteenth centuries, it was obvious that the system of factory production was dramatically different to anything which had ever existed, but it was thought that might disappear just as suddenly as it had emerged.

Marx was the first major economist to see that the accumulation of capital in factories represented a new, permanent structure of the economy: capitalism. He developed a theory of the business cycle, the short-term fluctuations in economic growth, which is much more persuasive than the equilibrium-based theories which dominate academic macroeconomics today.

But he was completely wrong on a fundamental issue. Marx thought, correctly, that the build-up of capital and the advance of technology would create long-term growth in the economy. However, he believed that the capitalist class would expropriate all the gains. Wages would remain close to subsistence levels – the “immiseration of the working class” as he called it.

In fact, living standards have boomed for everyone in the west since the mid-nineteenth century. Leisure hours have increased dramatically and, far from being sent up chimneys at the age of three, young people today do not enter the labour force until at least 18.

Marx made the very frequent forecasting mistake of simply extrapolating the trend of the recent past.

In the early decades of the Industrial Revolution, just before he wrote, real wages were indeed held down, as the charts in Carney’s speech show. The benefits of growth accrued to those who owned the new machines. Marxists call this the phase of “primitive accumulation”.

But such a phase has characterised every single instance of an economy which enters into the sustained economic growth of the market-oriented capitalist economies, from early nineteenth century England to late twentieth century China.

Once this is over, the fruits of growth become widely shared.

In fact, Carney’s own charts give grounds for optimism and contradict the lurid headlines around his speech. One is headed “Technology driving labour share down globally”. In other words, the share of wages and salaries in national income has been falling. In the advanced economies, this was some 56 percent in the mid-1970s and is 51 percent now. But all the drop took place before the mid-2000s. If anything, the labour share has risen slightly since.

Similarly, inequality has increased over the past 40 years, but almost all the increase took place in the 1980s. Depending which measure we take, it has either stabilised or fallen since 1990.

The future looks more optimistic than either Marx or Carney suggest.