Hegemony has become a major aspect of today's foreign policy, it has taken the place of imperialism and empires. There are vast differences between Britain's Empire of the 18th and 19th centuries and the hegemon that has taken it's place during the 20th and early 21st centuries, The United States.
An Empire is a single nation that forcibly controls another nation, preferably lacking in strong central government, without specifically incorporating it into the country itself. The true definition of hegemony is the blurred distinction between primacy and overt domination, but in today's society, the term was chosen in an aversion of the negative connotation to the word Empire.
To completely define the difference between hegemony and imperialism it is good to compare two shining examples, Britain and The United States. Britain's rise to an empire was a long one. The island had been attacked and defended for centuries, keeping it on the cusp of militaristic technology. With this power it was easy to spread influence, first by expanding the navy to control trade routes, then by enlarge the size of the infantry, allowing conquering of land.
Over time, the empire became too big and because of a combination of excessive wars, slave and peasant revolts, and length of communication. Communication was an imperative factor, it took far too long to be efficient, thus slowing response times to the aforementioned problems. This pattern of expansion has become all to familiar throughout history, from the Romans to the ancient Chinese Dynasties.
The dawn of The U.S.'s imperialism has happened at a time of great economical, technological, and social changes. All of the problems encountered by the previous empires, especially Britain, have been bypassed, creating a potentially unstoppable nation. The matter of communication has been overcome, two people on opposite sides of the world can hold a conversation in real-time.
Slave and peasant revolts are an obstacle that took a little more careful planning. To keep those at home satisfied, they are constantly bombarded with a constant flow of propaganda from privatized media. The government's proposal to privatize the internet as well would completely seal the citizens from the truth.
The revolts overseas are prevented by never actually sending troops to control a territory. All around the world, The United States has been able to control other governments through a series of coups d'etats, threats, and debts. In the rare occasion, when the first three do not accomplish the intended purpose, preemptive strikes and wars are used. By using coups d'etats, threats, and debts, which are more often than not successful, The United States Government also reduces the necessity of war and use of resources.
Not only have the ways in which hegemony and imperialism are conducted been changed, but also the process of profiting from such actions. The previous form of profit, used by Britain, was the tributary system. It was very simple and straight forward, it involved controlling a nation and forcing them to pay a tax or tribute to keep the empire from attacking the region. Today, it is much more complex. In oil-rich third-world countries, The United States convinces the nation that the key to their success and eventual ability to feed it's people lies in certain investments such as a dam, a power plant, or oil-refinery.
The nation, in good trust, takes The United States' recommendation and hires the job out to a U.S. contractor, also recommended by The United States. Once the nation realizes the massive cost in such endeavors, The United States immediately offers to loan the money, fully knowing they won't be able to pay it back. After several attempts to collect the money, The United States settles on receiving oil or other commodities at a dramatically reduced price, reducing the nation's profits and creating the exact opposite of the original promise of making the nation wealthy.
The definition of a hegemony and an empire has been hotly debated over the past few decades. Some believe a hegemony is a tactic to avoid the word empire and the negative connotations that are associated with it. Others believe that a hegemony is a more technical, well thought out form of an empire. Some believe it is a lesser form of imperialism. Although one thing that is not disputed is the fact that hegemony very well is a form of dominance over a smaller, weaker nation, and no matter what one may call it, or how it may be approached, dominance will continue to flourish through the ages.