Imagine I'm a small child because I'm having some trouble getting my head around it. As I understand it they are part of the UK in all matters except as regards importing and exporting goods because the border for that now runs through the Irish Sea.
How the fuck can that work? I mean, what are the logistics of it? Can they seriously not buy goods from another part of their own country without import/customs duties? And who would they pay customs duties to?
Have they been completely sacrificed for the convenience of the UK govt? Surely life is going to be a bit awkward in this sort of half-way state.