Political Impediments to Environmental Accords: The Tragedy of the Commons and Externalities

Despite a strong scientific consensus regarding the negative environmental and economic consequences of climate change, politicians face immense difficulty in constructing multilateral political accords to address these challenges.
This difficulty is particularly evident in attempts to reach agreements to limit $CO_2$ emissions among various states.
There are three primary sets of political impediments to reaching these accords, the first of which is the phenomenon known as the "Tragedy of the Commons."

Definition: The Tragedy of the Commons is a situation that encourages the overuse of common pool resources because individuals making consumption or use decisions do not bear the full social or aggregate costs of their individual overuse.
Common Pool Resources include:
    - The atmosphere.
    - Bodies of water (rivers, lakes, oceans).
    - Fisheries.
These resources are characterized by the fact that it is extremely costly to limit or restrict their consumption by individuals or groups.
The tragedy emerges specifically with public property or resources that are commonly held rather than privately owned.

Scenario: A factory emits high levels of $CO_2$ into the atmosphere because it utilizes coal as its principal energy source.
In this scenario, the atmosphere is the commonly held resource being utilized and degraded.
Localized Impact: The factory pollutes and degrades the air quality in its immediate locality.
Economic Constraint: It is costly for a city or locality to restrict the factory's consumption of the atmosphere. If a city forces the factory to shut down or move to another state or country, it loses the jobs created by that industry.
Divergence of Interests:
    - A clear divergence emerges between private benefits and social costs.
    - It is often viewed as "irrational" for an individual polluting firm to take on individual responsibility for conservation.
    - Risk of Foregoing: If a firm chooses to forego the consumption of the common pool resource, they risk the resource running out before they can use it because other actors will continue to consume it.
    - Competitive Disadvantage: A factory owner may observe that competitors in different states or countries are not paying the costs to transition to cleaner energy (like solar power). Paying investment costs to move away from coal may drive the owner out of business by increasing costs in the short and long run.

Competition in Fisheries: Governments often provide subsidies to fishermen to ensure they remain competitive and to facilitate capital investments in fishing equipment designed to increase catch sizes.
International Pressure: If one government offers such support, it pressures other governments to implement similar policies to protect their own fishing industries.
Absence of Agreement: Without a multilateral agreement among governments to control these subsidies, there is a lack of incentive for private conservation.
Collective Outcomes: While each fisherman makes a rational individual decision to accept subsidies to increase catches and profits, the aggregation of these decisions leads to the depletion of fishing stocks and the erosion of the common pool resource.

Simple taxes are generally insufficient to solve these challenges due to "distributional implications."
Market Intervention: Any government intervention into the marketplace results in winners and losers among different groups.
Hypothetical Scenario: An upstream factory dumps pollutants into a river that serves as a vital water resource for a city.
    - The Dilemma: The factory provides essential jobs and economic stability, but it ruins the water supply, causing illness or forcing citizens to pay for expensive treated water.
    - Optimal Allocation: Determining the efficient or optimal allocation of resources over the long run is complex.
    - Cost Responsibility: If a policy forces the factory to assume all costs of adjustment (e.g., changing production processes), the factory might go out of business. However, the city is currently subsidizing the factory because the factory's cost function does not account for the "true social cost" of production, such as the health hazards of unsafe drinking water.

The central challenge is the difficulty of defining property rights over common pool resources like rivers.
Lack of exclusive rights leads to overuse and limits the incentives for conservation.
Comparison to Private Land:
    - A farmer who owns 1,000 acres of land exclusively has an incentive to maintain it.
    - Farmers may let portions of acreage lie fallow or rotate crops to regenerate soil nutrients.
    - Because they hold exclusive rights, conservation directly improves the long-term sustainability and value of their natural resource.
In contrast, no single entity holds exclusive rights over a river or the atmosphere, so conservation incentives are largely absent.

Definition: An externality is a cost or benefit of an activity that accrues to third parties who are not direct participants in any exchange relationship relative to that economic activity.
Example: A factory produces a chemical to sell to a plastics factory in China.
    - Third-Party Impact: People living in the town who do not work at the plant and do not buy the chemicals still suffer from degraded water quality.
    - These are the "social costs of production" that are not borne by the factory owners or managers.
    - The factory enjoys an advantage by distributing its production costs across the entire community.
Global Application: Similar dynamics apply to carbon emissions from coal-burning electrical stations in locations such as Kentucky, West Virginia, China, and Texas.
The fundamental question for policymakers is how to prevent individual firm decisions from collectively imposing severe environmental degradation and social costs that all of Earth's inhabitants must eventually bear.