Why is globalization inevitable? Is globalization desirable or undesirable?

Nothing is inevitable, except death and taxes. As Hume pointed out, we live in a probabilistic universe with multiple possible outcomes. Realistically though, some outcomes are more probable than others. Long-term, civilizations around the globe are becoming more intertwined--economically, technologically, and socially. In the estate of nature, human society was local. Settlements were small and based on hunt-gathering. With the agricultural revolution, stored wealth became possible, and people specialized according to opportunity, talent, and interest. A shoe maker, for example, would trade his work for the produce of a farmer. Similarly, countries with certain specialized advantages engage in mutually beneficial trade. The Roman Empire became the first international political system. To adjudicate trade disputes between merchants from various Roman city-states, they developed a common law system (i.e. those laws in common to all governments). Their system broke down during the feudal era, resulting in more tariffs and less trade. Today, international law consists mostly of treaties, without regard to a universal theory of equity. This removes the ideal element from international law, tempting participants to vie for protection of their favored interests. Whether this results in a new Dark Ages, remains to be seen. With increased population, trade, and communication, the long-term trend is toward a global society. There are counter-reactions, as people of different cultures are exposed to foreign thoughts, which were previously less known to them. There will be setbacks on the way to an integrated global society. Further reading: Ancient Law by Sir Henry Sumner Maine. https://en.wikisource.org/wiki/Ancient_Law

First and foremost, it is a very big claim to state that globalization is inevitable. Globalization is a social construct and is, by definition, the exchange of ideas—cultural, technological, economical, financial—between peoples and nations that have allowed individuals from all parts of the world to become more interconnected. As a social construct, globalization succumb to change and is dependent on the world's conscious choices and efforts.
Whether globalization is viewed as desirable or undesirable depends heavily on how one personally evaluates and weighs out the pros and the cons. Proponents of globalization often argue that it creates a better world for everyone financially. Free trade among countries allows for the promotion of global economic growth, increases opportunities for jobs, and drives prices down for consumers. Another pro is that globalization is beneficial for poor countries, as their adoption of technology and foreign capital may provide them the opportunity to develop economically.
In terms of cons, one of the primary complaints is that is creating a greater rift between the rich and the poor, where the rich are becoming richer and the poor are becoming poorer. Another problem globalization generates is that jobs originally offered in developed countries are now lost and being transferred to developing, lower-cost countries.
Before coming to your own decision on whether globalization is desirable or not, it is important to evaluate both sides of the argument and weigh out the benefits and the risks.
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