When it comes to economics, Marine Le Pen is well to the Left of the French Socialists. She wants wealth taxes, nationalisation, higher social spending and tariffs.

Globalisation, the National Front leader told the crowd at her campaign launch in Lyons, meant "manufacture by slaves for sale to the unemployed". This is almost the precise opposite of the truth. Globalisation – free trade, to give it its less loaded name – always brings net benefits to the countries that practice it. There are losers as well as winners, true; but the losers are necessarily outnumbered by the winners. And those losers are generally not skilled manufacturing workers. Rather, they tend to be the lowest-paid immigrants, often in the textiles sector. Madame Le Pen would have been more accurate to describe globalisation as "a way to tackle France's chronic unemployment by creating many more well-paid jobs in exchange for exporting a smaller number of badly paid jobs".

But, of course, this isn't really about economics. It's about sentiment: a feeling, common to many Western countries, that change has come too quickly. It's worth remembering that the word "protectionism" was not coined as an insult. It was used by supporters of tariffs who knew that the desire to protect – to fence in, to nurture, to shield – is deeply embedded in human nature.

Free trade runs up against a million years of evolution. The instinct to provide against famine, to hoard, is encoded in our genome. The fact that free trade works wherever it is tried – compare autarkic North Korea to open South Korea – doesn't make it any less counter-intuitive.

Marine Le Pen knows that the protectionist instinct, never entirely absent in any society, has been especially strong since the 2008 crash, which convinced many voters that the system was rigged against the little guy. She has cleverly tied her economic arguments to her hostility to immigration, appealing to every French voter who thinks that the doors have been left open for too long. "On est chez nous!" yelled the crowd at her rally. "This is our home!"

Those of us who recognise that specialisation and comparative advantage make everyone better off, and who see benefits in legal immigration, should none the less acknowledge the power of that sentiment. I remember a French friend, a conservative MEP, responding to television images of the mass movement of peoples into Europe last year by reciting a couplet of Victor Hugo's:

Marine Le Pen
Far-right party National Front leader Marine Le Pen attends a press conference on January 27 in Denain, France Getty Images

D'autres auront nos champs, nos sentiers, nos retraites;
Ton bois, ma bien-aimée, est à des inconnus.

[Others will possess our fields, our pathways and our bowers;
Your woods, my beloved, will belong to strangers.]

In fact, though, Mme Le Pen is offering more of the medicine that sickened the patient. Protectionism and welfarism are the causes of France's troubles. The French budget has not been in balance since 1974. In order to defend the privileges of state employees, successive governments have allowed the country as a whole to become less competitive, more strike-prone, more sclerotic and poorer.

It's the same story every time. Protectionism inflicts the greatest harm on the least well off – who are often, paradoxically, its supporters. The Corn Laws were a massive wealth transfer from the poor to the rich. The Smoot-Hawley tariffs brought misery to America's workers. Today's anti-market agitators – the Trumps and the Tsiprases as much as the Le Pens – will find the same thing.

The true solution to France's malaise is the one thing that hasn't been tried there – at least, not since the mid-nineteenth century – namely a free market. Sadly, no candidate is seriously proposing it.

Daniel Hannan has been Conservative MEP for the South East of England since 1999, and is Secretary-General of the Alliance of European Conservatives and Reformists