I have long argued that we are unlikely to trade less with the EU after we have left than we do today, whether we have a special deal or not. Clearly the rest of the EU will want to keep on selling their goods to us, so they will not be able to impose big barriers on trade. Nor can they under WTO rules. Both the rest of the EU and the UK will remain under WTO rules on our departure.
The good news about offering the rest of the EU the choice between confirming current tariff free arrangements and registering it as a Free Trade Agreement at the WTO, or accepting most favoured nation status with low average WTO tariffs is that either outcome will be fine from the UK point of view.
This obvious commonsense does not prevent some “experts” claiming we might lose trade and therefore they think lose some output. Indeed, one or two extreme Remain enthusiasts have suggested all trade with the continent will cease if we leave without an agreement, an absurd proposition. Trade will continue. Germany will not stop selling us cars nor France her dairy products.
It is interesting, however, to ask what happened to the UK economy when the extreme outcome did occur. In 1939-40 when war broke out with Germany, Germany soon took over much of the continent by conquest. It was also in alliance with the Axis powers, which included Italy, Hungary and Romania. The Axis countries and the conquered lands did not trade with the UK, so for a period there was no trade between the UK and most of the continent.
What happened to the UK economy? It leapt ahead, growing by 32% in real output and income between 1939 and the peak in 1943. Much of the growth in output was of course production of military transport and weapons. By 1943 the UK was producing a staggering 26,000 planes a year from widely dispersed component and assembly factories around the country. By the end of the war the UK had also developed the first jet engine fighter, and had produced 250 Gloster Meteors. Output of military vehicles, ammunition, military clothing and much else was massively increased.
The UK was also turning out large quantities of commercial shipping. There were strong advances in coal and steel output to fuel and supply the industrial activity. Much of this was paid for by public spending and public borrowing.It would have been equally possible to expand civilian production with private sector spending and lending if there had been no military imperative.
What 1939-45 demonstrated was the potential in the UK to have a much larger energy and industrial sector if the demand was available and if imports from the continent were closed off. The country also converted much more land to agriculture to produce much more of its own food.
Fortunately we will not be revisiting those extreme times. We can ,however, learn from them that the UK is very adaptable, and could also adapt in more benign conditions where it would be good if we produced more of what we want and import less from the rest of the EU. I doubt they will want to impose tariffs on their exports to us to encourage us to produce more of our own goods and farm products.