" when a First World nation crashes out of a trading bloc."
You mean, like when the UK pushed Australia, New Zealand, Canada and other commonwealth countries out of a free trade block when it entered the EEC?
Well, New Zealand never got over it: to this day we run around in bare feet and live in caves and think the world is a dark and dangerous place ruled by magic, esp outside of the 'shire.
Note to those who haven't studied any economics: when your currency falls through the floor, tourists flock in and your exports are in demand, esp if they are still "cheap" after the EU applies a tariff.
Danish pork will become expensive, making UK pork look like good value. We call this "import substitution".
(Incidentally, this is why the Euro is proper-fucking the PIIGS: they can't trade their way out of a slump, because their currency can't fall...)