posted this at ars forum: (it should be clear I think it was a stupid move by the WH, but I am trying to think what might have "informed" it)
Steelmanning the risks, its the link to mainland as a weakness in supply chain of power, compared to onshore sources possibly. But, the construction is in close water, well inside the exclusive economic zone. You would think passage of a craft capable of causing a power shock with an anchor chain was raising hackles well before this, because it's hugely unusual for a warcraft of another nation to be that close without an explicit permit. Under the Jones act, all inshore commercial craft delivering goods to and from named ports have to be US badged, for international shipping it's clear from the baltic there's a concrete risk, but that's a matter of policing the boats, not banning the structures at risk.
A second steelman might be some belief about the intermittency. Thats easily knocked over because the system as a whole is building out storage and continuity systems, is adapting to a mix of technology with different power availability throughout the day, and of all the sources of power, wind is one of the most easily predicted to a useful window forward. You know roughly when a dunkelflaut is expected inside 48h, if you don't know exactly when, or for how long. Thats well north of the spin-up time for alternative (dirty) sources of power, if your storage capacity isn't there yet to handle it.