One problem that both fiat and commodity backed currencies have is exponential debt growth. This always leads to debt deflation when the overburden of debt gets so large that it sucks all the money out of the economy. All the different 'isms' have this problem. The only solution is debt cancellation. With private control of credit creation, management never allows their assets (the bonds they hold) to be torn up. And so they demand public assets when the nation's debts cannot be paid. Thus the problem with private monopoly control of credit at the national level. Transfer of publicly held lands, infrastructure, etc to private oligarchs simply by the inevitable consequences of monopoly private credit creation. It is dysfunctional to operate economies this way. The nations must retain or recover their sovereign right to public credit creation. This allows publicly held debt to be cancelled, when it grows so large that it sucks all the money out of the economy in interest payments. But currently this is not the case, and so we see massive problems in Europe at the present, precisely because of private control of credit creation at the national level.
Usurpation of democratic, public national control by private interests, in the form of banking legislation.