The greater part of the good that we constantly create through our interactions is unavoidably externalised. We create objects, environments, ideas, sensations, discoveries, relationships, commitments, and reassurances. These do not rest in our individual bodies, nor are they necessarily distributed equitably or freely. Their destiny, after externalisation, is emergent and open to contest.
The cognitive and practical activity of politics is the contest over this externalised product of human life in pursuit of desire, which includes sex but also self interest and morality. The measure of politics is credibility, in other words we invest our life's product in the political system that most credibly allows us to fulfil our desire, and credibility includes coercion. The system with the most credibility gets invested with most of the human product, and wins.
Capitalism recognises and celebrates the externalisation of life's product, and in this respect is most realistic. Capitalists compete to control a maximal amount of life's product, not to use it but to compel those with less to interact with them positively. Thus they seek power, a degenerate form of the sex instinct that gives refuge from the fear of sidelining, at least for men. Capitalism has high credibility because it delivers this refuge to all but the poor, and because it uses violence to ensure a supply of compliant poor. Capitalism is well served by a single hierarchy, and therefore seeks globalisation.
Socialism acknowledges the externalisation of life's product but seeks to regulate it equitably. It succeeds, but fails to provide a compelling answer to desire. The best that Socialism does is to provide security through collective norms and assets, turning a social group into a haven in which desire could flourish. The credibility of Socialism is high in small groups, but falls as the group enlarges because empathy is replaced by conservatism or opaque power as a cohesive force. Socialism has not yet managed to deploy a global model with credibility comparable to Capitalism.
Anarchism denies the externalisation of life's product, or harbours the mystical belief that no particular attention needs to be paid to its distribution. Instead, it celebrates the fulfilment of human desire in a true way, and not in the surrogate way of Capitalism or the tentative way of Socialism. It is thus the most compelling but also the least credible of the three systems, because it offers no analogue to the robust experiences of power or regulation that the other two systems put forward as refuge from individual frailty.
So Capitalism wins. In order to improve matters the Left has to articulate some plan that is at once as celebratory of desire as Anarchism and as credible as Capitalism. So far the Left has only come up with the compromise of Socialism, but there is hope. Technology changes the emergent patterns of externalisation of good, and Feminism moves the subject of desire away from patriarchal men. Perhaps these factors will shift the balance of credibility towards a system where desire can be fulfilled.