Daniel Hannan is an MEP for South-East England, and a journalist, author and broadcaster. His most recent book is What Next: How to Get the Best from Brexit.

To grasp the full extent of Venezuela’s tragedy, consider just one statistic. In 1959, GDP per head in Venezuela was 10 per cent higher than in the United States. That’s right. Venezuela wasn’t just the richest country in Latin America; it was one of the richest countries on the planet.

When I was growing up in Peru in the 1970s, Venezuela was the place people aspired to emigrate to. Not just from South America, either. People came in their tens of thousands from southern Europe in search of a better life.

One man, even during those plentiful years, fretted about the future. Juan Pablo Pérez Alfonzo, a former Venezuelan energy minister and a founder of OPEC, pronounced what now looks like a spookily apt prophecy in 1976: “Ten years from now, 20 years from now, you will see, oil will ruin us.”

In the event, he was out by 20 years: the ruin came in the 2000s. And for once the word “ruin” is literally accurate. Inflation in Venezuela is running at ten million per cent. There are verified deaths from malnutrition. Far from importing immigrants, the country has lost three million people since Hugo Chávez’s Bolivarian revolution, the worst refugee crisis in the history of the Western hemisphere.

What caused a collapse on this scale? Was it the “resources curse”, the name economists give to Pérez Alfonzo’s theory that unearned wealth wrecks an economy? Was it, as Corbynistas are now claiming, external sabotage? Or was it something else?

It is certainly true that oil can have a devastating effect on a country’s political system. Think of Iraq, Iran, Nigeria or Russia. Politics becomes a scramble for what Pérez Alfonzo called “the devil’s excrement”. To be more precise, the politicians who can place themselves between oil reserves and oil companies can make such vast fortunes that they can buy elections with their loose change.

But the “resources curse” is not inevitable. It did not destroy democracy in, say, Norway or Alberta. Several Gulf states – perhaps because they are aware of Pérez Alfonzo’s gloomy thesis – are now careful to place some of their oil bonanzas in sovereign wealth funds, aimed at diversifying their economies.

In the case of Venezuela, the spike in the cost of a barrel of oil during the early Chávez years had the effect of temporarily masking the worst effects of his policies. “There are no good or bad presidents,” Venezuelans say, “only presidents when the oil price is high, and when it’s low”. Chávez, needless to say, did not use his oil bonus to diversify the economy or build up reserves. He used it to cover the massive costs caused by his imposition of price controls, nationalisation and exchange controls. Anything he had left over went to backing Leftist insurgents elsewhere in Latin America. It was during those early years that the international Left (not only Momentum types) lectured the rest of us about how the rest of us ought to copy the Venezuelan example.

When the oil boom ended, the calamity of the command economy caught up with Venezuela. Like every other socialist strongman in human history, Chávez had made people poorer. Much poorer. Stories of hunger and emigration spread, opposition groups were harassed or closed down, but overseas Leftists still wanted to support the regime. So they began to claim that US sanctions were to blame. In fact, the only US sanctions in place before August 2017 were asset freezes and travel bans aimed at a handful of Chavista politicians and their cronies. (Many of the children of Venezuela’s socialist élite have scandalised their countrymen with their conspicuous consumption at luxury resorts around the world, and Chávez’s daughter is said to be worth four billion dollars.) There is no way that such personalised micro-sanctions could conceivably have harmed the Venezuelan economy as a whole. Even after 2017, eight years into the economic crisis, the sanctions were extended only to a ban on buying government bonds or bonds in state-owned enterprises.

Incredibly, though, Corbynistas are still sticking to their line that the cataclysm is all America’s fault. A letter in last week’s Guardian railing against a US-backed “attempt at regime change” was signed by, among others, three members of the Shadow Cabinet.

Ah, the eternal, unthinking, catch-all Corbynista response: “But America”. Never mind that Maduro’s Bolivarian regime has now been disowned by most of the world. Never mind that almost all Latin American and European countries have recognised Juan Guaidó as acting president. Never mind that Maduro’s last remaining friends include Russia, Iran and North Korea. Jeremy Corbyn’s first rule is that Everything Is Always America’s Fault.

It is important to understand how far Labour has now moved from the mainstream Left. Guaidó is no conservative. He is a social democrat, whose party is affiliated to the Socialist International. Governments of the democratic Left around the world have recognised him because they acknowledge that the last Venezuelan presidential election was a travesty. Even Ecuador, a Bolivarian state that, following the Chavista playbook, scrapped its old constitution and “refounded” itself on socialist lines, has withdrawn its support from the Maduro racket. But old Jezza is sticking to his Cold War nostrums. Any enemy of America is a friend of his.

The idea that Venezuela has been wrecked by external sabotage is bonkers, recalling the language of Stalinist show-trials. I mean, suppose you truly wanted to sabotage Venezuela’s economy. How would you go about it? What, from the outside, could you realistically do?

Venezuela’s economy has been wrecked, not by fascists, counter-revolutionaries or imperialist running dogs, but by socialism. Taking control of the means of production, distribution and exchange has led to the same outcome that it always does: destitution. Yet this is the regime that Jeremy Corbyn and Diane Abbott and John McDonnell saw – still see, even now – as their model. God help us.