This economic model is defended from a Marxist perspective, which states that a planned socialist economy can only emerge after first developing the basis for socialism through the establishment of a market economy and commodity-exchange economy and that socialism will only emerge after this stage has exhausted its historical necessity and gradually transforms itself into socialism.[9] Proponents of this model argue that the economic system of the Soviet Union and its satellite states attempted to go from a natural economy to a planned economy by decree without passing through the necessary market economy phase of development.[10]