Hi, I mostly lurk, but I thought I would post a defense of planned economies. I'm pretty much a socialist, though I personally have issue with the idea of a planned economy (I'm closer to a syndicalist in thought), but here are the essential lines of argument against a free market/in favor of a planned economy.
1. Capitalism is very efficient in generating profit, but profit does not always equal the same thing as being the most efficient at providing service. As an example, private health insurance is typically more expensive to run than government run plans per person, because of greater administrative overhead in claims processing. While having this administrative apparatus leads to the health plans being more profitable for the shareholders, it soaks up more capital and labor then it would if it were simply government controlled.
2. Waste caused by competition. Coke and Pepsi, to use an example, spend billions per year advertising when everyone older than a child already has an established preference for one or another. Drug companies spend more money marketing their drugs than they do actually researching new medicines. In a market without competition the capital and labor used towards these functions would be freed up for use in human needs (or building a bigger war machine, if you desire a dystopia).
3. The inherent efficiencies in a monopoly. Now, in the long run, monopolies do lead to corruption, higher prices, etc. But even capitalist businesses want to become monopolies. Just as when a company makes a purchase of another, and integrates management, it cuts cost, an entire sector of the economy with integrated management should, in theory, be more efficient by an even greater degree. An example my Trotskyist friends say is a nation with one airline would need fewer planes, because they would not need to offer competing (and partially empty) flights. This would lead to substantially cheaper ticket prices.
4. The centralization leading to a loss of incentive to work is not needed, though it may have been true in the Soviet system. In a properly managed socialist economy, workers become more efficient and work harder to shorten their workweek and have more time for leisure, rather than for a wage incentive. I find the idea that greed is inherent to humanity always somewhat farcical. Sure, humans have a desire for status and recognition for their accomplishments, but there are societies without money or private property. A properly engineered economy could create these status rewards without excessive monetary compensation. Also note that in a capitalist system, raises are not given neccessarilly for hard work, but just about any reason the boss wants, unless there is an explicly stated policy. Merit pay generally *does not* cause harder work than companies that have seniority systems.
a quibble: There is no such thing as a 'free market'. Even the wildest libertarian dream provides for a system of property rights, including intellectual property that by their very nature cannot be neutral. In an actual lawless state a market would be impossible, as contracts would be unenforceable, and companies could settle disputes with violence. What a ‘free market’ entails is a set of property rights that is in favor of established ownership over communal control.