There has been a sea border between the Canary Islands and the Spanish mainland since Spain joined the EEC in 1986. As a bureaucratic nuisance it ranks somewhere between the Northern Ireland Protocol and the Windsor Framework. However, it caused little aggravation – 'EU special status' was even seen as an advantage – until online shopping allowed all two million Canarians to experience the nuisance themselves.
Getting the apparently mundane issue of consumer parcels right has far more political significance than might have been anticipated, which is why Westminster's mishandling of it is such an ominous sign.
The Windsor Framework fudges many issues, expecting the improved UK-EU relationship to sort them out later. But its approach to parcels contains genuine solutions and should be seen as a success.
The problem is broken down into three categories.
Parcels sent by individuals from Britain to Northern Ireland will have all sea border requirements waived.
Parcels sent by businesses in Britain to customers in Northern Ireland (covering online shopping) will have all requirements waived for the business and the customer. There will be collection of sea border data but by the shipper, under a new scheme for authorised postal operators.
The third category, parcels sent by businesses in Britain to businesses in Northern Ireland, is not a success. Full sea border requirements apply, unless the business in Britain registers with the trusted trader scheme to use the green lane. Neither option will be economic for many suppliers.
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However, this is a fiasco for business and government to fix. Few consumers will experience it directly or link it to the impact on cost and choice, at least to an extent that causes routine aggravation.
The EU passed a law in June implementing its side of the deal. Its legislation clearly sets out the three categories and how they will be treated differently.
Yet no such distinction is made in the equivalent UK law, now in its final stage at Westminster. All parcels sent from Britain to Northern Ireland are simply to be classed alongside "foreign postal packets".
No further clarity is added by the explanatory notes to the legislation. Nor would the government explain itself to a House of Lords scrutiny committee.
The committee includes no unionists or Brexiteers but does include former SDLP leader Baroness Ritchie. Last month, it complained of lack of information and consultation and said it could discern no rationale for rushing the law into effect this August. The Windsor Framework deadline for the new parcels regime is September next year.
Matters came to a head this Monday in a Commons committee, which is meant to be used for swift passage of uncontentious laws. The government realised half its 10 MPs on the committee were Brexiteers and likely to object, so it replaced them at the last moment.
This led one Tory Brexiteer to call his government "bent", while DUP MP Sammy Wilson denounced the legislation as "part of the jigsaw in removing Northern Ireland from the UK".
Only then did a minister assure the committee of the three categories approach. It was too late: Mr Wilson retreated to the Commons chamber, where he joined DUP colleague Gavin Robinson in calling for a parliamentary debate.
Robinson is a moderate and leadership loyalist. His unease reflects how much harder it has just become for the DUP to return to Stormont.
Why would the government create such an unnecessary problem? It must be due in part to Westminster's supine tendency to give Brussels more than it needs, a weakness that ironically provoked Brexit. The easiest way to enact the Windsor parcels deal is to apply full restrictions in law, then waive them by agreement. That does not make it the only way, or force the government to be uncommunicative to the point of being provocative.
Of course, the government is also in its dying days; hurried, divided and distracted, and thoroughly sick of the DUP.
Nationalists will presumably be happy to agree with Mr Wilson that the law is taking Northern Ireland out of the UK, but that is hardly guaranteed. All the row has definitely achieved is to make it less likely Stormont will be restored in the short term and the Windsor Framework can function in the longer term, as that requires trust and cooperation.
It is easy to see the DUP deciding to sit on its hands until next year's general election sweeps the Tories out of office. Notably, Labour abstained on the parcels law in the Commons committee.
