As dawn breaks over Sydney tomorrow, the first protesters will appear on the city's streets, draped in yellow and blue. Soon they will be joined by people in Tokyo, Istanbul, Paris, London and New York. 

This weekend, protests against Russia's invasion of Ukraine are expected globally. But can ordinary people really make a difference? 

The journalist Thomas L Friedman believes the war will end in one of three ways. 

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

The second is a compromise. If Ukraine promises to give up territory and never join NATO, Russia agrees to a ceasefire. 

There is one final possibility: "salvation". The Russian people, with the support of the rest of the world, bravely stand up to oust Putin and end the war. 

Throughout history, people have acted together to overthrow oppressive leaders. 

The American Revolution began in 1773 when protesters stormed onto a ship in Boston Harbour and threw its shipment of tea into the sea. In 1986, one million Filipinos forced President Ferdinand Marcos to flee to Hawaii in the People Power Revolution. 

And just three years later, months of public protests in Germany led to the fall of the Berlin Wall.

Research suggests that when just 3.5% of a population actively participates in peaceful protests, they never fail to bring about change. If five million people march in Russia, Putin's 22 years in power could end. It is not impossible.

But not every protest movement is successful. Huge protests in Europe against the invasion of Iraq did not stop the war. Even Friedman admits that salvation is the least likely option. 

The stakes are high. There is no doubt: what happens now could transform Europe for centuries to come. 

Yes: Every successful protest movement in history has relied on millions of individuals making up their own minds to act and support a cause. 

No: Ordinary people alone cannot change an entire political regime. Political leaders must act too. 

Or... The end must come from 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.

Thomas L Friedman - Friedman has worked for The New York Times since 1981. He has won three Pulitzer Prizes. 

Nato - The 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.

Ceasefire - An end to fighting - often temporary.

Ferdinand Marcos - The 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.