This 11 September - 'La Diada', National Day of Catalonia - Barcelona's Avenida Diagonal thoroughfare overflowed with around two million people in an unprecedented mass mobilisation.
Once again, the people of Catalonia have seized the streets. To shout loud and clear their rejection of the repression of the Spanish state. To call for the freeing of political prisoners and return of those in exile. And to demand that the republic they voted for overwhelmingly on 1 October 2017 at last be realised.
This human tide in support of the Catalan republic contrasts with the resounding failure of events organised by the Spanish-nationalist Catalan Civil Society civic group and far-right Vox party, and the right-populist Ciudadanos party.
The pathetic images of Ciudadanos leaders - received by barely a hundred of their supporters in the city centre - sum up the failure of these reactionary Spanish-nationalist elements. They attempt to declare themselves the voice of the "silent majority" of Catalan society - but have been put in their place.
The leaders of the reformist left must take note - the party chiefs of Podemos and Izquierda Unida (IU - United Left), the tops of the CCOO and UGT, the two biggest unions - and also the leaders of the Catalan-nationalist ERC party. The contrast between this tremendous show of force and the tiny capacity for mobilisation shown by the defenders of the post-Franco 'regime of '78' could not be more abysmal!
How is it possible to go on maintaining that "it would be stupid" or "it's not possible" to take the republic forward because Catalonia is divided 50/50 - like Joan Tardá, ERC deputy in the Spanish parliament, and Pere Aragonés, ERC vice-president of the Catalan government, recently have?
Faced with the impossibility of hiding the success of this Diada, the capitalist media - Spanish and Catalan - chose to recognise it. But they attempted to present it as just another day, minimising the numbers participating.
The leaders who spent months propagating the idea that it's not possible to realise the republic because "there is not sufficient strength"- the leaders of PDeCat, the main party of Catalan capitalism, its JxCat electoral alliance, and the ERC - have received an inarguable answer.
This massive mobilisation was even more significant when you take account of the fact that it came after a year of constant repression by the Spanish state apparatus.
This has included political trials; exceptional measures like 'article 155' of the constitution, which suspends the power of the Catalan government; and the refusal of the Spanish state's ex-social democratic PSOE party government to accept the right to self-determination for the people of Catalonia.
Most importantly of all, it came after three months of cold water being poured on the movement. The approach of rejecting participation in actions on Diada has also been adopted by Barcelona mayor Ada Colau, and the leaders of Catalunya en Comú, the Podemos-IU Catalan electoral alliance.
In unjustifiable declarations, Ada Colau and the leaders of Podemos said Diada reinforces 'unilateralism' and the division of Catalan society. In practice, they renounce the principle of the right of the Catalan people to decide their own future. This is a right which not so long ago they defended, and which won them mass support from the population.
This political turn brings them in line with the Spanish-nationalist parties of '155'. It has provoked surprise and revulsion among the vast majority of the workers and youth who voted for Colau and the local Barcelona en Comú electoral alliance including herself, Podemos and IU.
Their failure to support the liberation of the people of Catalonia with a consistent policy - linking the struggle for a Catalan republic with the fight against the capitalist regime of '78, and for workers' republics in the rest of the territories which make up the Spanish state - is a grave error that will cause great difficulties.
The mass force demonstrated on the streets collides ever more clearly with the tendency of certain political forces to seek to hold back the movement. These are the forces which look for agreements from above - agreements with a state and a government that refuse to negotiate anything other than the movement's surrender.
The dissatisfaction with this situation is shown by the proliferation of slogans on posters and stickers, like "make the republic now!" and "self-determination is not negotiated, it is exercised" and so on. It is also shown in the criticisms made by speakers from the pro-independence Catalan National Assembly civic group, the left-nationalist CUP party and others.
This once again confirms that within the movement for Catalan national liberation there are two fundamentally opposed political approaches.
The first represents a small minority, but today it sets the pace and dominates in government. This approach attempts to put a brake on the movement and reach an agreement with the Spanish capitalists - which would mean shelving the Catalan republic.
Confronting this approach is the immense majority of workers, youth, and broad sections of the middle classes. They want to advance towards a republic of workers, youth, and the people, in order to see a solution to the current social problems, and a break with capitalism as well as the regime of '78.
For that to happen, the left needs to struggle for leadership in the movement for national liberation, on the basis of a socialist programme and fighting to sustain the mass mobilisations, to unite the majority of the Catalan working class.
In particular, this requires including those layers hit by the crisis of capitalism who reject the reactionary ideas of the PP, the main party of Spanish capitalism, and Ciudadanos - but who so far distrust the independence movement because of PDeCat and the Catalan right, from whom they have only received attacks and cuts.
Today, more than ever, it is essential to build a united front of the left to struggle for a socialist republic of the workers and youth - bringing together the CUP, the Committees for Defence of the Republic, combative trade unions, women's rights movements, students, and social movements - in order to carry the movement forward to victory.