Interesting and cool headed thread I would agree in principle but two points make me think that this description doesn't picture the scale of the drama correctly.
For one, it misses that Britain's economy is building up on the current arrangements - SM premium access is the foundation of it. Especially for supply chains, upcoming changes can easily become a killer. For one they work on the basis of comparatively small profit margins. /1
A significant increase of costs can easily lead to redundancy: why keeping factory ß in A if B provides much better profit margins? And massively subsidising sectors needs to be financed: tax rises and / or loans (w/ decreasing credit rating) aren't a proper solution. /2
Just have a look on CMEA's breakdown after downfall of USSR: parts of the problem of Eastern European economy was that they were fully adjusted to economic / trading arrangements which fully broke down. /3
Second, to adjust takes time and a lot of sources & effort. I somewhat doubt that it is a proper foundation of a national effort if half of the country (the ones with - on tendency - more money and better education) thinks the other part went nuts. /4
Forcing people who already oppose those changes to pay for them won't work. It's easy to see a gridlock of reforms and an emerging blame game. Besides, having hostile relations and being desperate for new arrangements with others rarely need to adequate alternatives. /5
Besides, in such a scenario you might have to face serious efforts by EU to unpick and lure out business. With already drained sources it is at best difficult for UK to answer adequately. /6
And also the individual costs of opportunity don't point to an happy end: labour is also without FoM moveable. Especially highly skilled labour will find it comparatively easy to leave the country. In case of serious economic issues, individuals might find ... /7
... that the argument to stay and work on a national project (you may not even believe in) is less convincing. Same with money: rising taxes significantly in times of economic problems might invite tax evasion of a new scale. Money is even more flexible than people. /8
So in a way you face an emigration issue in a no deal situation. How on earth shall constitutional and economic changes be financed under those conditions with a potential social as well as political gridlock. /9
Leaving this point aside, UK might even face more problems with secession movements which will be difficult to calm without having those reforms (and even then it would take time until their effects kick in). In NI you might even face a revival of violence. /10
On that mark: if UK's infrastructure turns out to be massively inadequate to deal with a no deal scenario and you get shortages of any kind which can't be solved or fixed that it get back to normal within few days or weeks, u might find that ppl can become really unpleasant. /11
Problem essentially is not "WTO terms" but it's consequences for a developed economy and a society which is used to those economic terms. /end
