Answer to Question 3:

Suppose that there is incontroverible scientific evidence that carbon emissions will polute the atmosphere and seriously harm residents of this planet in generations to come. Does it make sense to have the government tax all activities that produce carbon emissions in proportion to the damage they will do and rebate the sums collected back to individuals in the community in a manner that will leave the distribution of income unaffected?


The proposal would seem an obvious way to deal with this negative externality. Producers of emissions would adjust their outputs downward in response to the increase in their costs or develop ways to produce without causing emissions. One can see, however, the political difficulties of setting up such a system. A large fraction of people in the economy will suffer reductions in their current incomes. Imagine, for example, what might happen to the prices of gasoline and heating oil! Less current aggregate output will be produced because the post-policy production techniques were available before the policy was instituted and were deliberately not used. The beneficiaries of the program, whose benefits may be far in excess of current costs, will be distant subsequent generations. Would you expect the public support such a policy?

It turns out that if a single small country alone is adopting the policy there is little to be gained by its future generations. The overall effect of one small country reducing its carbon emissions on the total emissions on planet earth is likely to be very small. Indeed, as the small country's residents face increased costs from domestic production of goods for which emissions are substantial, there will be an incentive for them to import those goods from countries with no carbon tax, exporting in return those domestic goods whose production does not involve the creation of carbon emissions.

The negative externality is international in scope. Domestic residents who create carbon emissions do not bear the full cost---a large fraction of the cost is born by future generations who will live in countries other than their own. To eliminate this externality, appropriate taxes on carbon emissions must be levied in every country in the world and, if income distribution effects are to be avoided, the resulting revenues would have to be given lump-sum to world residents in a fashion that will leave the distribution of world income unchanged.

Can you imagine all countries agreeing to this?

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