LONDONDERRY, Northern Ireland — Crossing the border between Northern Ireland and the Irish Republic used to involve delays, checkpoints, bureaucratic harassment and the lurking threat of violence. That it’s now virtually seamless — that you can drive across without even knowing it — feels close to miraculous.
It is also one of the great successes of the Irish peace process of the last several decades. “It was like you had to climb over a locked gate,” George Fleming, the president of the Londonderry Chamber of Commerce, said in an interview. “And then someone came and opened the gate.”
But as with so many British-related matters these days, “Brexit” — Britain’s divorce from the European Union — has thrown this hard-won arrangement into jeopardy.
If the British government succeeds in extricating itself from the European Union, the two parts of Ireland will lose one of their most important connective threads: a shared membership in the bloc. In an instant, one part of the island would be in Europe, and the other would not.
Established nearly 100 years ago according to political expedience rather than natural logic, the border — some 300 miles long, with about 210 crossings — is not easy to control, police or even always identify. (Many of the crossings are on tiny back roads.)
Reinstating a hard border, as residents call it, would have both psychological and practical implications. The movement of goods and services between north and south, now commonplace and easy, would become far more complicated with the introduction of new tariffs and customs regulations.
