The day of global solidarity with the Occupy Wall Street protests in New York on 15 October marked the emergence of a new movement with a rejection of capitalism at its heart. Protests were held in over 950 cities across 80 countries and five continents with over a million people taking part.
But impressive as this is, the ideological impact was even greater. The atmosphere has already been transformed more than once this year already. The democratic revolutions in Tunisia, and especially Egypt, reasserted the collective power of the masses to defeat dictatorships. The mass strikes in Greece and the youth-led rebellion of the Spanish "indignados" signalled a new willingness to challenge austerity.
But now, by targeting Wall Street, the heart of US financial power, a debate about the very nature and legitimacy of capitalism as a form of society has been reignited. The frustration exhibited by much of the media about the occupiers' supposed lack of demands reflects a nervousness within the ruling class that it is the system itself, rather than one or other aspect of it, which is being called into question.
This new movement has echoes of the anti-capitalist movement that emerged following protests against the World Trade Organisation in Seattle in 1999. But today's protests take place in a much altered context. As Seamus Milne noted in the Guardian, "While the 1990s anti-capitalist globalisation protests took place at a time of boom and speculative frenzy, today's occupations are targeting a global capitalism in the deepest crisis."
This gives the protests a sharper edge. Rising unemployment means a generation of young people are facing a sharp clash between their hopes and their increasingly grim future prospects. It also means the protests have gained an even wider resonance among millions of people experiencing an increasingly intractable economic crisis that they are being forced to pay for.
One reflection of this is the way the new movement is launching open-ended occupations of public spaces rather than focusing on set-piece mobilisations in opposition to gatherings of the global elite at G20 or IMF meetings.
The protests also raise major questions about the liberal democratic system - the very model people in North Africa and the Middle East are being told to adopt - and its failure to be genuinely responsive to the needs and wishes of ordinary people while slavishly promoting the interests of the corporate and financial elite.
The rising curve of working class resistance in 2011 also offers the prospect of bringing together workers' struggles and an anti-capitalist movement.
Here in Britain unions across the public sector are gearing up for what will effectively be a one-day public sector strike on 30 November, the biggest industrial confrontation between organised labour and the government since the 1984-5 miners' strike.
This occurs against a backdrop of a renewed debate about the inability of the capitalist system to met the basic needs of millions of people, even in the richest countries. This fact will help boost workers' confidence in the legitimacy of their fight.
In France in May 1968 the immense collective power of workers at the point of production came together with young people angry at the system as a whole to shake the foundations of the system. But it occurred in a system that had enjoyed a quarter of a century of expansion, where unemployment in the advanced industrial countries had largely been banished. Today we face a capitalist system in crisis following three decades of neoliberal restructuring. Socialists have to seize on every opportunity to challenge that system.