And yet, such situations lead to market-failure situations.
For the most part, I'm a free-market capitalist. But every philosophy has an error if you take it to the extreme. In the case of pure capitalism, you cannot deal with "market failures" (in particular: externalities, monopolies, cartels, tragedy of the commons...) with purely market-driven economics.
Its a known fact. The only solution to market failures is to stop using the market as a tool.
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Government policy should be to default to capitalism, but if an externality (or other market failure) is identified, you should use the Government as a tool to correct the market failure.
Ideally, you should minimize the Government's enforcement. Regulation is poorly accepted by the lay population who fail to understand its importance. But since 3rd party intervention are provably the ONLY solution to a market failure (indeed: its the DEFINITION of a market failure: when a 3rd party has to intervine)... your choices are as follows:
1. Accept the market failure as reality. (Ex: allow monopolies to exist. Allow externalities to warp the costs. Etc. etc.)
2. Create a 3rd party (usually Government) to regulate or force people to leave the market driven approach.
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> The same can't be said for involuntary trades, like those that filter through the government. This is the situation we're discussing right now. The government took your money and spent it on some pet project, probably tied to a donor.
Case in point for market externality: City A uses up too much water from a river, such that City B no longer has enough water to survive. Gathering water from a river is extremely cheap, and maybe City A and B lived in peace before... but today cities can grow exponentially. And the increased usage by City A has led to City B's downfall.
This is a realistic situation on the Colorado River, where cities upstream have taken so much water that the Colorado River no longer flows to the ocean. To ensure that cities downstream even get enough water, there is a multi-city and multi-state agreement to ensure that Nevada, California and Arizona split the water appropriately.
Unfortunately, the agreement is flawed. But some agreement is better than no agreement at all.
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The free market "solution" is that City A gets all the water, because its upstream. There's no reason for City A to cooperate with City B, any cooperation at all means that City A (from a free-market perspective) "loses" water that it feels like it deserves.