The final question for this series is whether any of the issues brought up by the Frankfurt school still have any currency or importance. There are two distinct periods in the work of the Frankfurt school. On the one hand there is the attempt to explain and understand fascism as it was arising during the Weimar Republic. This was a period of social, economic and political dislocation that brought to the fore very real material concerns on the part of workers that could easily be channelled into a traditional search for scapegoats and simple explanations. During this period, however, there continued to exist a powerful workers' movement in the form of social democracy and communism which, had it been able to overcome the timidity of the former and the strategic incompetence of the latter, could have functioned as a bulwark against the rise of the extreme right.

The second period is that of the postwar years, in which there was a social consensus that was formed under the umbrella of the cold war and rising prosperity (what the French call Les Trente Glorieuses) and in which it was declared that class and class struggle had come to an end. Frankfurt school theories about commodification, alienation, reification and false consciousness were revived by the 1968 movement as a way of explaining away the apparent passivity of the working class. Indeed, it was during this period that the working class began to be seen as part of the problem rather than the solution. The forward march of labour was halted, social democratic and communist parties accommodated to the new consensus and, as the philosopher André Gorz had it, it was "farewell to the working class".

Since the mid-70s, however, we have again been living in a different world in which the automatic prosperity and growth of the postwar decades have disappeared. Real wages have fallen at the same time that productivity has risen, thereby transferring unimaginable wealth to the richest in society. Estimates of how much money is stashed in offshore accounts vary between $12 and $32tn – enough wealth to wipe out almost all the social problems of poverty in one fell swoop were it to be confiscated, socially invested and redistributed.

The problem now is that the two original periods that characterised the battleground for the Frankfurt school exist at one and the same time. We have the economic dislocation of the Weimar period with rates of unemployment in Europe rising constantly (Spain, for example, has reached over 50% youth unemployment), which is feeding into a rise of neo-fascist and rightwing parties from Golden Dawn to Ukip. At the same time there is a supine centre-left which is tied into the neoliberal agenda, while a fractured and fragmented "communist" movement (for want of a better word) has failed to put together a convincing alternative.

The great recession since 2008 has stripped away a lot of the illusions people have about the society they live in. When a government needs to proclaim that "we are all in this together", then it is clear what the true subtext actually is.

But perhaps even more seriously, the planet itself can no longer afford the constant expansion required by capital. We have the technological and financial means to solve pretty well all of the basic problems of humanity. What we don't have is the political will. But that is only missing because even our hopes for the future have become privatised and commodified. Our dreams have been bought up and sold back to us as glittery tat and royal weddings. It has often been said that it is easier now to imagine the end of the world than it is to imagine a better one.

But this was true at the start of the Frankfurt school. Theodor Adorno wrote:

"The prospective fascist may long for the destruction of himself no less than for that of the adversaries, destruction being a substitute for his deepest and most inhibited desires … He realises that his solution is no solution, that in the long run it is doomed. Any keen observer could notice this feeling in Nazi Germany before the war broke out. Hopelessness seeks a desperate way out. Annihilation is the psychological substitute for the millennium – a day when the difference between the ego and the others, between poor and rich, between powerful and impotent, will be submerged in one great inarticulate unity. If no hope of true solidarity is held out to the masses, they may desperately stick to this negative substitute."

That loss of hope and optimism about a better world is the most depressing outcome of the current crisis and it is no wonder that many seek refuge in the false nostalgia of an unspoiled world before the ravages of capitalism prompted "all that is solid to melt into air".

But there is no way back, not least because the golden age never existed and the golden dawn will never come. The only way is to push forward using science, reason, intelligence and hope. Weak power may be good enough for now but at some point someone is going to have to flex muscle. Let's make sure that it is the good guys and not the fascists again.