The moon landing. The JFK assassination. Lilith the lynx escaping from Borth Wild Animal Kingdom. Everyone says they knows where they were during these seismic moments in human history.
While the resignation of Conservative minister Priti Patel probably won’t live as long in the memory, those who do remember it will know precisely where they were. They were on Twitter.
So how did we get to the stage where a politician’s downfall was so absorbing it probably dented Britain’s GDP?
Let’s recap ...
Patel, the UK’s international development secretary, got into hot water after she admitted to holding meetings in Israel while on holiday in August, including with Prime Minister Benjamin Netanyahu.
However, the Foreign Office was only made aware of the ‘secret’ meetings on August 24 - after they took place.
The problem here is that Patel could have been seen as freelancing and making government policy on the hoof.
By Tuesday night, amid increasingly loud calls for her to resign, things got appreciably worse.
Except removing Patel from her ministerial berth for breaking the ministerial code was problematic for Theresa May, chiefly because they were more than 4,000 miles apart.
Patel was on an official trip to Uganda, and firing a colleague while in another continent when you don’t have a parliamentary majority is probably not good form.
Why she was in Uganda in the first place is itself intriguing.
Undeterred by geography, May ordered Patel to abandon her visit, and it was briefed a nine-hour flight from Nairobi in Kenya to Heathrow had been hastily arranged.
Meanwhile, the MP’s recall left a Daily Telegraph journalist high and dry.
British political Twitter swiftly identified a Kenyan Airways Boeing 787 Dreamliner was probably carrying the imperilled Secretary of State.
But back on terra firma, more allegations were ping-ponging around.
And there was more ...
This time in Patel’s favour: the Jewish Chronicle reported how Number 10 instructed Patel not to include her meeting with an Israel foreign ministry in her list of undisclosed meetings.
If true, it would have meant Downing Street had in effect lied to journalists.
No. 10 flatly denied the story. Regardless, Patel may well have been blissfully unaware of the unfolding crisis.
“There is no wi-fi on board”.
Patel’s epic journey was now more than just Twitter fodder. The state broadcaster’s interest was very much piqued.
But it wasn’t just journalists tuning in.
That’s right, 22,000 people were tracking her flight live online on a working Tuesday, and updates were constant.
People started to imagine how her arrival in London might play out.
BBC News broadcast live pictures of Patel’s plane as it landed at Heathrow ...
... but Patel managed to side-step awaiting reporters.
Ah, but helicopters ...
Was everyone going too far, though?
There was a break in the drama as Patel was forced to wait for more than an hour as May met the Queen for her weekly audience at Buckingham Palace.
But Patel eventually arrived by Downing Street’s back gate.
After a 33-minute meeting, the inevitable came.
But was it all worth?