A crowd of thousands.
The residence of the nation's leader sealed off behind black metal fencing and a line of police in riot gear.
And the sense that a great movement of the human spirit has once again caught the leadership off guard and flapping...
The unexpected has happened. Let's hide.
The British added a little refinement of their own- sealing the roads into Whitehall with lines of police cavalry.
Now if there's one thing that symbolises the power of the British State at its most brutal it's a policeman on horseback. Mrs Thatcher deployed mounted police against demonstrators in London, as earlier against striking miners at Orgreave. It may have been what finally did for her- that spectacle of armed men riding down unarmed civilians in Trafalgar Square. The British have a long memory. They saw that and thought, "Peterloo".
Symbolism counts. It counts against the powerful.
I don't know whether Mr Johnson was tucked in behind his lines of steel- or putting his feet up at Chequers- but as so often since he became PM he was conspicuous by his absence from the heart of the action. Like the Duke of Plaza-Toro he has "led his regiment from behind, he found it less exciting." Priti Patel stood in for him- and mouthed the sentiments that other politicians around the world are finding useful at this time- something along the lines of "won't you please think about your health." The world is waking from the sleep of centuries and nanny says, "wrap up warm and don't forget your handkerchief." No, it's not an adequate response. Nor is it leadership. It brings those who voice it- and the offices they hold- into contempt.