Luke Harding and Andrew Roth at the Guardian say that the Russian poisoning was not about the victims but all about the message.

One former employee of the Russian special services said nerve agents were used only if the goal was to draw attention. “This is a very dirty method. There’s a risk of contaminating other people, which creates additional difficulties,” he told the Kommersant newspaper, adding: “There are far more delicate methods that professionals use.”

In other words, novichok was a gruesome calling card. As those who organised the hit must have known, the trail goes directly back to Moscow. The incident even took place down the road from Porton Down, the government’s military research base, which swiftly tested and identified the toxin.

Why? There are various theories. To pick a fight with the UK while playing the victim card, perhaps; to motivate rich Russians to go back to Russia…to scare potential witnesses in the Mueller investigation.