Realism is one of the oldest and most popular theories in international relations. It offers a perspective on competition and power and can be used to explain actions between states. An example of realism is the United States' reaction – or lack thereof – during the 1994 Rwandan genocide. All branches of realism share some central principles. Realists believe that the world exists in a state of anarchy. Since there is no world government that prevents states from attacking each other, or punishes them when they do so, it becomes very important that each government is able to protect itself and ensure its own survival. It is also why states are considered the most important actors in realism. Because of anarchy, the world operates in power and is extremely important. If a state has military power and, to a lesser extent, economic power, it is able to defend itself and even influence other states. Realism emphasizes the importance of a state being more powerful than its competitors. In realism, states are seen as rational and unitary actors. Realists assume that a state's actions are representative of the state's entire population, ignoring political parties, individuals, or conflicts within the state (Goldstein & Pevehouse, 2010). Any action taken by a State aims to pursue the national interest. National interest is “the interest of a state as a whole (as opposed to particular political parties or factions within the state)” (qtd. in Goldstein and Pevehouse, 2010, p. 355). If a state is rational, it is able to perform a cost-benefit analysis by evaluating the cost versus benefit of each action. This assumes that all states have complete information when making choices (Goldstein & Pe...... middle of paper ....... the S. sent troops to Rwanda, US troops would die. Some they argue that it was worth it, however, to save thousands of other lives. Works Cited Baldauf, S. (2009) Why the United States Did Not Intervene in the Rwandan Genocide [online] Retrieved from: http://www.csmonitor. .com /World/Africa/2009/0407/p06s14-woaf.html [Accessed: 21 February 2014].Goldstein, J.S. & Pevehouse, J.C. (2011 Boston: Longman.Gordon, M. & Friedman, T. (). 1993 ). Details of the US raid in Somalia: a success so close, a loss so profound [online] Retrieved from: http://www.nytimes.com/1993/10/25/world/details-of-us-raid. -in-somalia-success-so-near-a-loss-so-deep.html [Accessed: 21 February 2014]. United Human Rights Council (2014 Genocide in Rwanda /www.unitedhumanrights.org/genocide/). genocide_in_rwanda.htm [Accessed: February 21 2014].