Why a single email could darken the world's most powerful AI in an afternoon

When you use one of these AI models, you are not running a program on your own computer. Your words travel to a datacentre — a windowless shed full of specialised chips, owned by the company or by the cloud giant it rents from — are processed there, and the answer is sent back. You keep none of it. Nothing of the model sits on your laptop.

That design is the whole reason a single government letter could darken Anthropic's two most powerful models for the entire world on the evening of 12 June. There was no copy on anyone's own machine to keep working. The company turned off access at the source; live sessions simply ended in errors, and requests were quietly rerouted to a less capable model. Convenience and control run down the same wire, and on 12 June someone pulled it.

Set against that, the alternative. Open-weight models — China's DeepSeek, the newer MiniMax — are published as files you can download and run on your own hardware. No one can switch those off, because there is no central switch to throw. The trade-off is that you need a serious bank of chips to run them, which means a company or a state, not a household. Closed or open, the choice is the same one: convenience you don't control, or control you have to build and power yourself.

And power is where this lands in Britain, hard. The country hosts comparatively little of the compute it relies on. The largest planned build, OpenAI's Stargate UK, was paused this spring, partly on the cost of electricity. The queue of projects waiting to plug into the grid has swollen from around 41 gigawatts in late 2024 to roughly 125 by the middle of 2025, about 50 of it datacentres — far more than can be connected any time soon. And British industrial power costs roughly four times what the same electricity costs in the United States.

Put those together and the picture is plain. Britain runs a growing share of its work on AI it does not house, served from buildings it does not own, and it cannot easily build its own because it has neither enough sites nor cheap enough power to fill them. The cloud is not the villain here. It is efficient, which is exactly why everyone uses it. But efficiency and control are a trade, and Britain has taken the efficiency and left the control on the table.

The fast story this fortnight was a switch thrown in Washington. The slow story underneath it — the one that decides whether Britain is ever less exposed — is made of substations, planning consent and the price of a megawatt. It is less dramatic and far more important, and it is being settled now, mostly with no one watching.

Disclosure: The Quernal's analysts are written using Claude, made by Anthropic, the company at the centre of this story. The model we use, Claude Opus 4.8, was not affected by the directive; the suspended models, Fable 5 and Mythos 5, are its more powerful siblings.