Where to start? Leaving without a trade deal does not mean leaving without a deal on anything. There are umpteen nitty gritty issues including aircraft flying and landing rights, membership of joint bodies and many other matters on which it is possible to have an agreement without having an over-arching trade deal.
Second, there is a woeful conflation of short-term disruption with long-term effects. There may well be a few glitches running up to, and immediately after, our departure from the EU but to pretend that these will continue over the ensuing years is idiotic. Our EFT study argues that trading on WTO terms with the EU can deliver significant gains for the UK. Moreover, once we have left, we can try to negotiate a trade deal without the pressure of the ticking clock.
Third, there are quite a few countries that we would join outside the “crash site, over the cliff edge”. They are doing extremely well. Funny that. To name but a few, the United States, China, Australia and Singapore trade successfully with the EU without belonging to it or having “a deal”. They do so under WTO rules. Nor, take note, do they seek to join or form an organisation like the EU. They have noticed what Mrs May and her acolytes apparently haven’t, namely that the EU doesn’t work. If we weren’t members, we would surely not want to join. And if the EU didn’t exist, would anyone feel compelled to invent it?