Its not up to the UK. Its unlikely the EU would let them back in so soon, and if they did the UK would be in a weak bargaining position so they wouldnt get all the opt outs and exemptions they had before. Also EU progressives seek greater integration and the UK was the loudest voice against it. Its a lose lose.
As its been 8 years from the vote and the paperwork still hasnt been figure out, its probably going to be another 20-30 years until things have simmered down enough that people can objectively look back and say it was the worst decision in modern history without people getting all pissy and defensive (most of them will have died of old age). Then they can apply to join again.
Northern Ireland might get back in sooner though. Maybe Scottland as well, but less likely.
Yeah Northern Ireland could basically just vote to join Ireland.
Scottland would have a harder time. As much as i support the idea they would have to leave the UK, develop an economy good enough to meet the joining criteria (might need to create their own currency), then get permission to join from all member states, including the ones with seperatist movements which dont want to be seen as lenient towards seperatist causes.
It is possible as they could likely use the Euro in the mid term (but this would cause their borrowing rates to be higher than if they had their own currency, as they have no control over monetary policy) and maybe the countries with seperatist movements wouldnt care as they’re leaving the UK. But its a bit of a gamble…
Edit: added clarification about currencies
As a European, it seems reasonable to me. I think the UK should let one or two generations pass to assess its true power, influence, and wealth in the world before making any major decisions. Similarly, the EU needs to find its own way, see how far it can go without the UK (and possibly without the tutelage of the USA), and thus determine what concessions it might need to make to the UK in a negotiation and what aspects would be non-negotiable.
I so hope the Tories loose so badly, that the Lib Dems become the largest opposition party. They at least are for rejoing the EU and would argue for it.
Well, he is 61. Even if Britain starts the process of rejoining right now, chances are high that he won’t see it.