The old view of economics
In Smith’s day, people saw national wealth in terms of a country’s stock of gold and silver. Importing goods from abroad was seen as damaging because it meant that this wealth must be given up to pay for them; exporting goods was seen as good because these precious metals came back.
So countries maintained a vast network of controls to prevent this metal wealth draining out – taxes on imports, subsidies to exporters, and protection for domestic industries. The same protectionism ruled at home too. Cities prevented artisans from other towns moving in to ply their trade; manufacturers and merchants petitioned the king for protective monopolies; labour-saving devices were banned as a threat to existing producers.