“All terrorists are politely reminded that this is London and whatever you do to us we will drink tea and jolly well carry on. Thank you.” It was hard not to smile at the messages such as this that appeared online in the wake of Khalid Masood’s murderous rampage through Westminster. How ineffably British. The stiff upper lip. Keep calm and carry on.

Only in China could there already be a museum of internet finance. Though most Britons have barely adopted the term “fintech”, online banking is old hat in Beijing.

These are among the many, many things journalists like to say are “unprecedented” about the administration of President Donald Trump. Yet all the things I have just written could equally well have been written about Richard Nixon’s administration.

It was almost exactly 52 years ago, on March 8, 1965, that the first American combat battalions came ashore at Da Nang, South Vietnam.

“Breaking rocks in the hot sun / I fought the law and the law won.”

‘In the small hours of one morning,” Fanny Stevenson recalled, “I was awakened by cries of horror from Louis” — the author Robert Louis Stevenson. Thinking he was having a nightmare, she woke him up. “Why did you wake me?” he said angrily. “I was dreaming a fine bogey tale.”

America is living through a kind of Trumpian Genesis: seven days of high-speed political creation. In the beginning Trump created heaven (for his supporters) and hell (for the mainstream media).

President Donald J Trump’s favourite Twitter hashtag is #MAGA, which of course stands for “Make America great again”.

Imagine if George Washington’s farewell address had been followed a day later — rather than 172 years later — by Richard Nixon’s first press conference as president-elect.