Eighty thousand cheering supporters turned on a dictator in seconds

On 21 December 1989, Nicolae Ceaușescu, communist dictator of Romania for over two decades, mobilised 80,000 people into Bucharest's central square for a rally meant to prove the nation still loved, or at least feared, him. Riots had already broken out days earlier in the city of Timișoara, and revolutions were sweeping through Poland, East Germany and Czechoslovakia. Ceaușescu climbed onto the balcony he'd used scores of times before, flanked by his wife Elena, and began another dreary speech about the glories of Romanian socialism. Eight minutes in, mid-sentence, thanking the organisers of the event, he suddenly stopped, eyes wide, frozen. Somebody in the crowd had booed.

Within seconds, more boos joined it, then whistling, then a chant: 'Ti-mi-șoa-ra! Ti-mi-șoa-ra!' Ceaușescu shouted 'Hello! Hello!' into the microphone as though it were malfunctioning. His wife scolded the crowd to be quiet; he turned and yelled at her, live on national television, to be quiet herself. The broadcast crew, defying orders to cut the feed, pointed the camera at the sky but kept the sound running, and the whole country heard the collapse unfold in real time. Within days, the regime fell.

Yuval Noah Harari uses this moment to make a claim that runs against how we usually explain human power. It isn't raw intelligence that separates our species from chimpanzees or wolves; individual humans aren't dramatically smarter, and by some measures Stone Age humans were sharper than we are today. What separates us is a specific, rarer ability: flexible cooperation among large numbers of complete strangers, something bees do rigidly and chimpanzees only do within small circles of personal acquaintance.

But Harari's real twist comes after the balcony scene. Power didn't pass to the 80,000 people in the square, despite their numbers and their courage. It passed to the National Salvation Front, a group of mid-ranking former Communist Party officials who had no real ties to the demonstrators but did have decades of organisational experience and existing networks. The same pattern, Harari notes, played out in the 1917 Russian Revolution, where a Communist Party of just 23,000 members outmanoeuvred 180 million peasants and workers, and again in Egypt in 2011, where Facebook and Twitter brought crowds into Tahrir Square, but only the army and the Muslim Brotherhood had the organisation to actually take power once the square emptied. Numbers get people into the street. Organisation decides who runs the country afterward.

Start by looking at any cause or change you actually care about, in your workplace, your community, your own household, and ask honestly who already has the coordination, the roles, the follow-through, to turn energy into something lasting, rather than assuming numbers alone will do it. Put real time into building that infrastructure before you need it, the recurring meeting, the shared plan, the clear roles, instead of waiting for a moment of collective enthusiasm to carry the weight by itself. And test the apparent solidity of any group decision you're part of by imagining what would happen if one person spoke up against it first, because Ceaușescu's eighty thousand supporters looked completely unified right up until the moment a single boo proved otherwise.