The actual Good Friday Agreement says very little about cross-border trade

George Eaton (on Twitter) trotted out a lazy misconception: "Surely the main problem is the Irish border (again) - IIRC we can't be in EFTA and also (as required by the GFA) in a customs union with the EU."

Fraggles points out in the comments: "The GFA does not state that NI must be in a customs union with the EU. It simply doesn't. Who keeps making this stuff up?"
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In such situations, I find it useful to write down what you know, and look up what you don't.
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