Here’s an interesting insight from Joan Robinson on free trade. According to her, when Keynes rose to popularity, the thing that worried economists the most was actually that it was against free trade.

Keynes had a chapter on mercantilism in the General Theory, but is the most ignored. Perhaps economists don’t want you to find out!

The book The New Mercantilism (a lecture from 1965, first published 1966) starts off like this:

I began to read for the Tripos in the last decade in which the doctrine of the universal benefits of free trade was still dominant. It was imposed upon our young minds as a dogma. We were being received into the fraternity of economists, who knew that free trade is right, unlike the silly plain man who supposed that protection might do his country good, and the misguided politician who supported the vested interests of particular industries. In the dark age before the light of Adam Smith dawned, there had been mercantilists who were both misguided, because they thought it proper for a government to operate in favour of the economic interests of its own country, though at the expense of others, and silly because they thought that it was in a country’s interest to build up a trade surplus by restricting imports. When Keynes attacked the dominant orthodoxy, one of the things that grieved my teachers most was that he should try to rehabilitate the mercantilists, thus damaging the claim of the free-traders to superior benevolence and wisdom.

What is the “new mercantilism”? Joan Robinson says:

…

Nowadays governments are concerned not just to maintain employment, but to make national income grow. Nevertheless, the capitalist world is still always somewhat of a buyer’s market, in the sense that capacity to produce exceeds what can be sold at a profitable price. Some countries have experienced spells of excessive demand, but this corrects itself only too soon. The chronic condition for industrial enterprise is to be looking round anxiously for prospects of sales. Since the total market does not grow fast enough to make room for all, each government feels it a worthy and commendable aim to increase its own share in world activity for the benefit of its own people.

This is the new mercantilism.