This thesis creates a new variable for threat perception built upon psychological concepts and then applies this new variable to the question of why leaders use military force in certain situations. The concept of threat perception has a long history in the field in terms of its effect on leaders choosing to use military force. However, while the concept of threat perception is inherently psychological, previous proxies for the variable have included only situational factors, which is highly problematic. By utilizing the Operational Code, this study creates a new threat-perception variable based on cognitive constructs. Using a sample of US presidents, this new variable is tested in two different ways. The first examines three psychological characteristics (need for power, in-group bias, and distrust) from Leadership Trait Analysis that are thought to influence the level of threat perception in a leader. The second examines threat perception as an explanatory variable for the use of force alongside three other important control variables (economic violence, presidential popularity, and US power). The use of force variable is derived from Meernik's Use of Force dataset with each case in the dataset representing an opportunity to use force. The psychological data are derived from the verbal material of US presidents using at-a-distance methods found in the literature. OLS regression and probit are used to model the research questions. The project finds that levels of threat perception are indeed affected by a leader's level of distrust, in-group bias, and need for power. In addition, the new psychologically-derived threat-perception variable is a very good predictor of a president's use of force: presidents with higher levels of threat perception have a much higher probability of using force when the situation presents an opportunity.

Thesis Completion




Thesis Chair/Advisor

Schafer, Mark


Bachelor of Arts (B.A.)


College of Sciences


School of Politics, Security, and International Affairs

Degree Program

Political Science



Access Status

Open Access

Release Date