Discuss whether national defence or a public park is the better example of a public good. [12]

However, there are certain aspects of parks that fail to make it a true public good. On the one hand, there is the fact that the park is rejectable, as one can choose whether they wish to take advantage of it, thus the park fails to fulfill at least one of the criteria to be considered a public good. On the other hand, parks are also not perfectly non-rival. While a small increase in consumption will not affect the next person’s ability to take advantage of it, a very large increase in consumption can lead to the park becoming crowded to the point of being unusable, thus making it, at the very least semi-non-rival. Moreover, there can be certain marginal costs associated with the park. Costs such as cleaning or maintenance are likely to increase with consumption as more people using the park will likely result in more trash and more wear of the facilities meaning that the cost of cleaning up the trans and keeping the facilities in proper condition will increase with use. Thus, while public parks have many of the characteristics of a public good, they most definitely do not have all.

National Defense is arguably an even better example of a public good. It has essentially no marginal cost as the cost of national defense is mostly correlated with geopolitical tensions and the area of land that must be defended rather than the population. Moreover, it is completely non-rejectable as, while within the borders of the nation, you will, regardless of your actions, benefit form the national defense. In terms of excludability, it can be argued that, at least at an individual level, national defense is somewhat non-excludable, since as long as someone is within the defended area, regardless of whether they pay their taxes or not, they cannot be stopped from benefitting from the national defense. National defense is also non-rival as, one person benefitting from the national defense in no way affects anyone else’s ability to benefit from the exact same national defense. Thus, it can be seen how national defense can be considered a public good.

However, even in the case of national defense, we can find some limitations. While we can add people to a given geographical area that is currently covered by national defense without any marginal cost, this is within bounds, as, eventually, if enough people are added to the same area the cost of national defense must go up or the quality of the service must go down, if only due to the congestion created by the additional people. Similarly, national defense cannot cover new geographical regions with people in them at zero cost since facilities such as military bases need to be build and supplies need to be transported there. In any case, the marginal cost of national defense, while very low, is not zero. Furthermore, national defense can be argued to be inherently excludable as it is only ever supplied to a given geographical area, usually within the nation. Thus, geographical areas of people who do not pay taxes towards the national defense can, and usually will, be excluded. As such, we can see how certain aspects required for a good to be considered a public good are not fulfilled by national defense.

Overall, I would argue that neither national defense nor public parks are public goods. They are both quasi-public to greater or lesser extents. In terms of which is closer to the concept of a public good, I believe that national is a better fit as, when taken at the level of a single nation that does not aim to expand its borders or the geographical region it defends, national defense manages to fulfill all of the criteria for a public good almost perfectly, thus as long as these two base conditions are established, it is a near perfect example. When compared to public parks which fail to fulfill the aspects of non-rivalry and non-rejectability to the same extent, national defense becomes the clearly superior example of a public good.