The comment is making fun of a proposal Boris Johnson once made about building a bridge from Scotland to Northern Ireland, which is considered borderline physically impossible as far as I understand.
Tunnel, no. It’s very feasible and practical from a civil-engineering perspective, but the economic value of a road connection between NI and Scotland has not been demonstrated to outweigh the economic cost of its construction.
What’s feesible? The tunnel or the bridge? I’d heard the tunnel wasn’t possible due to the particular geography of the channel. But a bridge? Now that I’d be interesting I seeing. There used to be a giants causeway across there in mythical times ...
