We know exactly what happens because it’s actually defined in treaties, specifically WTO rules will apply. The UK is a full member of WTO independently of the E

We know exactly what happens because it’s actually defined in treaties, specifically WTO rules will apply. The UK is a full member of WTO independently of the EU. It’s important to remember that “the deal” isn’t a thing that was mentioned on the pamphlet that went through everyone’s door before the referendum. That just said that the government will implement whatever the people vote for (which was to leave). It’s entirely something the necessity of which was made up after the fact, as a face-saving measure by a political class that badly misjudged the national mood. It is obvious to anyone who has ever negotiated for anything, ever, that no deal is better than a bad deal. Ask yourself why Remainers are so keen to take that option off the table and keep asking for extensions indefinitely.