In the end, determining what constitutes a nation is somewhat subjective. People may identify themselves as members of myriad nations, but even those identifications may change over time. And the strength of the identification also varies. The division between an ethnic group and a nation is a tricky one to make. To put it crudely, the moment that an ethnic group starts to view itself as a nation, it becomes a nation. The Kurdish people, for example, became a nation when they started thinking of themselves as an ethnic group with a common language, history, and culture that set them apart from the neighboring Turks, Arabs, and Persians.
Example: Nations and their attendant nationalism in many ways caused World War I. In the decades leading up to the war, several European nations struggled to assert themselves on the global stage. These conflicts ratcheted up the tension. The event that directly precipitated the war—the assassination of Austrian archduke Franz Ferdinand in 1914—was also the result of nationalism: The assassin was a Serbian nationalist trying to free his nation from Austrian control.
Changing Identities
A good example of how membership in a nation changes over time comes from the history of the United States. In the early decades of the Republic, many Americans valued their connection to their home states over an attachment to the federal government. People identified with and felt loyal toward Virginia or Massachusetts rather than with the young United States. This reluctance to identify with other Americans contributed to the Civil War. After World War II, Americans closely identified with the United States as a single nation of one people. But in recent years, the “red-state/blue-state” divide has caused some people to increasingly identify with “their America,” as opposed to the nation as a whole.
States
A state is a political unit that has sovereignty over a particular piece of land. Sovereignty is the ultimate power within a territory. So the state has the power to make laws, defend its borders, and enact policies. The state also exercises a monopoly on the legitimate use of force: No group within its borders can use force legally without the permission of the state. In the United States, we use the word state to mean something more akin to the word province (the difference being that American states have more political autonomy and power than provinces in most other countries). But political scientists use the word state as a synonym for sovereign governments.
Who is Sovereign
A state is the ultimate authority within a territory. Smaller political units—such as city governments—exist within a state, but ultimately the supreme power rests with the state. The governments of the city of Chicago, for example, or Orange County, California, have some power to enforce rules within their territories. However, these governments do not have the final say: Local governments are not sovereign because they are subordinate to the federal government of the United States and must abide by the government’s rules.