An Irish Sea fixed crossing? A bridge too far for us!

Leo Varadkar’s diplomatic response to topical chatter about a bridge across the Irish Sea — possibly or perhaps impossibly from Larne to Stranraer — was well-judged. Yes, it’s “worth examining”, but don’t expect Ireland to pay for it.

Civil engineers are excited by the idea; they’ve been busy citing comparable projects in the Far East and the US, some of which turn out on examination to be incomparable, given the unique nature of the sea bed — with its deep trenches and World War II ammunition dumps — and the region’s challenging weather.

The UK prime minister is an enthusiast, too, but it should not be forgotten that Mr Johnson has form on dodgy bridge projects.

As mayor of London, he was a leading cheerleader for a pedestrian-only €233.8m, 366-metre Garden Bridge across the Thames, originally the idea of his friend, the distinguished civil engineer Joanna Lumley.

A formal review of the plan challenged its cost estimates, its risk to public funds, and its value.

It was abandoned, but not before €50.2m of the public’s money had been squandered on it.

The potential benefits from a fixed crossing for Irish-UK trade and the likely cost of improved road networks at the two ports have yet to be examined, as have Mr Johnson’s motives in championing such a project.

Does he see it as a possible bridge across the troubled waters now swirling around at least three — England, Scotland and Northern Ireland — of the UK’s four nations? If so, he is pinning his hopes on a ruinously high-priced wrong answer.