Power is usually defined as the ability to impose one's will on others, or to pursue one's interests on the expense of others'. Violence or other kinds of force, or the threat of such force, can be used to exercise power (coercion).
Political analysis often personifies nation states as powers, discussing superpowers, great powers, second-order powers and "European powers", for example, with convenient simplicity as manifestations of Realpolitik. In Western thought these terms are generally qualitative terms. In current Chinese political thinking national power can be measured quantitatively using an index known as comprehensive national power. Chinese political thought also distinguishes between various forms of national power. In particular, hard power (military power) stands in contradistinction to soft power (economic or cultural or persuasive power).
States have always had variable levels of powers and a number of terms have been developed to describe this continuum.
- A hyperpower is a term for a state that is by far the world's most dominant (e.g. the United States today)
- A superpower is a state that is greatly more powerful than almost all other countries (e.g. the US and USSR during the Cold War
- A great power is a state that is one of the leading powers in the worl (e.g. 19th century Great Britain
- A middle power is a state that cannot dominate other states, but does have some international influence (e.g. Canada today)
Quotation'Power tends to corrupt, and absolute power corrupts absolutely'.
(Attributed to Lord Acton, 1887.)