The two nations that have embraced it most fervently are Venezuela and Argentina, which have both seen increasi...
The two nations that have embraced it most fervently are Venezuela and Argentina, which have both seen increasing state intervention in their economies. Despite wide-ranging price controls, they have the highest levels of inflation in the region, amid other serious problems.
But now, five years after the collapse of US bank Lehman Brothers, we may instead be witnessing the twilight of economic "neo-leftism" in Latin America.
Despite wide-ranging price controls, they have the highest levels of inflation in the region, amid other serious problems.
And before the end of the year, voters in both countries will have the chance to express their frustrations at the ballot box - although not yet to change their respective governments.
Argentina holds mid-term congressional elections on Sunday, while Venezuela has local elections on 8 December.
After nearly 15 years of the late Hugo Chavez's "Bolivarian revolution" - now in the hands of his successor, Nicolas Maduro - Venezuela faces chronic shortages of basic goods, intermittently alleviated by emergency imports from more productive nations.
This week, for example, it was announced that the country is to import Nicaragua's entire crop of black beans for this year.
Nonetheless, the government has accused its political opponents of causing the shortages, as part of what Mr Maduro calls an "economic war".
Venezuela has long been Latin America's inflation league leader, but its rate has surged strongly this year and is now close to 50%.
According to some definitions, the country is now entering hyperinflation territory, something last seen in the pre-Chavez days of the 1990s.
All those imports are taking their toll on Venezuela's foreign currency reserves, with just $21.4bn (__13.2bn) in the central bank's coffers, the lowest level in nine years.
But the government is making some heroic assumptions about its ability to turn the economy around.
The country's finance minister, Nelson Merentes, drew laughter from opposition politicians this week when he announced his 2014 budget, based on an inflation rate target of between 26% and 28%.
That's roughly equivalent to the "true" level of inflation in Argentina, as measured by independent economists, although the government's own discredited figures put it at just 10.6%.
However, President Cristina Fernandez de Kirchner's administration has done its best to make life difficult for those who dissent from the official view.
Her chief enforcer, Commerce Secretary Guillermo Moreno, has attempted to take legal action against anyone who compiles an alternative inflation index, alleging that the aim is to manipulate the markets by publishing false data.
Mr Moreno is also in charge of forcing Argentina's supermarkets to sell staple goods at artificially frozen prices. Since the beginning of June, 500 products have been subject to price controls.
In July, he went as far as imposing the temporary closure of four supermarkets for not complying fully with the price freeze, although the reason was that they had run out of some of the products, which is what tends to happen when goods are sold at below the market rate.
In fact, as in Venezuela, price controls have tended to provoke shortages of the items affected, including bread, while other basic goods have also been scarce.
In July, Mr Moreno's office issued a statement calling on Argentines not to eat tomatoes for 60 days because of a seasonal shortage.
But the commerce secretary's heavy-handed ways have been catching up with him. Last month, he was formally charged with abuse of power over his efforts to stop the publication of independent inflation figures.
Mr Moreno has always maintained that he was acting within his responsibilities.
But if found guilty, he could be jailed for up to two years and be barred from public office for twice as long.
Argentina and Venezuela are travelling on similar political and economic paths. But Argentina has not suffered as badly.
The country is still expected to register GDP growth of more than 3% this year, while Venezuela appears to be heading for recession again, with negative growth expected for the first time since 2010.
Politically, both countries have leaders struggling to uphold the legacy of an ideological soul mate. While Mr Maduro is the inheritor of the Chavez mantle, Ms Fernandez is following in the footsteps of her late husband, Nestor Kirchner.
But the Argentine president is set to disappear from the political scene at the next election in October 2015, since she is constitutionally barred from running for a third term. With her brand of Peronism expected to do badly in Sunday's polls, she is unlikely to secure the two-thirds majority in Congress that would allow her to quash that ban.
Ms Fernandez has lost popularity since her re-election in October 2011, when she secured 54.1% of the vote. However, recent opinion polls are suggesting she may have regained some sympathy from the electorate after she had surgery to remove a blood clot on her brain earlier this month.
Mr Maduro, for his part, was elected in April and does not have to face the voters again until October 2018. But opinion polls have indicated that if that election were re-run now, his narrow and hotly disputed victory over opposition leader Henrique Capriles would be definitively overturned.
In the meantime, there are signs that both leaders are holding back unpopular measures until after voters go to the polls this year.
Argentina's supermarket price freezes are due to expire at the end of this month, once the mid-term elections are out of the way.
At the same time, the Venezuelan currency, the bolivar, still appears overvalued, despite a devaluation in February, when Hugo Chavez was still alive and in power.
In fact, there have been seven devaluations of the bolivar since Venezuela embraced Chavez's "21st Century socialism", and analysts are forecasting that there will soon be an eighth - but not until the local elections have taken place.
BBC News | By Robert Plummer