As dawn breaks over Sydney tomorrow, the first protesters will appear on the city's streets, draped in yellow and blue. 

When the rest of the world wakes up, more people will join them, first in Tokyo, then in Istanbul, Paris, London and finally New York. Soon, the whole world will be on its feet, marching in unison. 

This weekend, protests against Russia's invasion of Ukraine are expected around the globe. But can ordinary people with placards and loudspeakers really make a difference? 

This war can end in one of three ways, argues celebrated journalist Thomas L FriedmanFriedman has worked for The New York Times since 1981. He has won three Pulitzer Prizes. . 

The first scenario is that Vladimir Putin destroys Ukraine, erasing its leadership, culture and the freedom of its people.

The second is a compromise. Russia agrees to a ceasefire in return for formal control over eastern Ukraine and a promise that what is left of the country will never join NATOThe North Atlantic Treaty Organisation was founded in 1949 to unite Western democracies in Europe and North America against the perceived growing threat of the USSR. It now has 31 members.. 

There is one final scenario: "salvation". The Russian people, with the support of the rest of the world, bravely stand up to oust Putin. Finally, they achieve "the dream that we dreamed when the Berlin Wall fell in 1989 - a Europe whole and free, from the British Isles to the Urals". 

Many believe salvation is possible. History is filled with examples of people who acted together like an immovable tide to overthrow brutal tyrants and oppressive regimes. 

In December 1773, protesters angered by taxes imposed in London stormed onto a ship in Boston Harbour and threw 342 chests of tea into the sea. The American Revolution had begun. 

In 1986, more than one million people took to the streets of the Philippines after President Ferdinand MarcosThe president of the Philippines from 1965 until 1986, Marcos was also notorious for suppressing democracy and shoring up corruption. However, the Philippines made major economic progress during his time in office. was declared the winner of a fraudulent election. Four days later, he fled to Hawaii. It is remembered as the People Power Revolution - when Filipinos reclaimed their country. 

And just three years later, months of public protests saw the end of the concrete barrier that had separated East and West Berlin for 28 years. Hundreds of people stood atop the Berlin Wall, pulling people over into liberation. 

Erica Chenoweth is a political scientist studying nonviolent protests. Her research suggests that when just 3.5% of a population actively participates in peaceful protests, they never fail to bring about change. The idea of five million people marching in Russia, or 25 million in Europe, does not seem impossible. 

"To be in a sea of people demanding positive social change is empowering and exhilarating," says one academic. 

Of course, not every protest movement is successful. On 15 February 2003, people in 60 countries demonstrated against the Iraq war. It was the largest protest event in history, but the war still went ahead. 

In Hong KongAn estimated two million people took part in pro-democracy, anti-government protests in 2019., weeks of pro-democracy protests failed to loosen China's grip over the territory. And for Ukraine, even Friedman admits that salvation is the least likely of his three scenarios. 

Whatever happens, there is no doubt that the stakes are high. The actions of the people now could transform Europe for centuries to come.

Yes: A crowd is made up of individuals. Every successful protest movement in history has relied on millions of people making up their own minds to act and support a cause. This time is no different.

No: The collective voice of millions on the streets is powerful, but ordinary people alone cannot change an entire political regime. Political leaders, inside and outside of Russia, must act too.

Or... This war must end within Russia, but it is the Russian people who face the most danger from protesting. Change may happen one day, but it is unlikely to occur soon enough to stop this war.