© Stephanie Lecocq/EPA
Any sort of border in Ireland, whether physical or regulatory, is politically impossible and publicly unpopular. That's bad news for hard Brexiteers.
Is Northern Ireland the first crack in the dam? There is no solution to hard Brexit along the Irish border. Negotiators have been chasing this will-o-the-wisp for over a year. They have not found it because it does not exist. A border is a border, it is not "not-a-border". It means barriers, checks, queues, papers, regulations, tariffs. No one wants it in practice. Does anyone want it in theory?
The trouble is politics. If Theresa May agrees special status for Northern Ireland to remain in a trading union with Ireland it will effectively "move the border" to Belfast. Her fragile Unionist coalition collapses. If the Irish prime minister, Leo Varadkar, fails to win such special status and sees a border installed, his confidence and supply government collapses. There is no way round this. It is the Schleswig-Holstein question of the age.
There can be no iron curtain across the Irish countryside. Not 10% of the British public would want that. Even the fiendishly complex use of electronic tags would still leave in place the fact that leaving a customs union would mean monitoring different tariffs and regulations north and south of the border. It would be a license to smuggling and piracy.
Comment: See? It happens to men too!