In the aftermath of the terrorist attacks on the World Trade Center Towers and the Pentagon The United States conducted combat operations in Iraq and Afghanistan. The U.S. government declared the major combat operations a success and important steps in the war on terrorism. Although it is true that the Taliban and Al Qaeda have been routed, the two groups have reorganized, adapted and are continuing to fight. Al Qaeda's operations were disrupted, yet the organization remains a viable transnational threat. Success in the war on terrorism is, therefore, more than the sum of battles and engagements. To define success in the war on terrorism, measures of success must be determined to achieve the strategic goals. Terrorism is not a unique phenomenon. It is merely a tactic of political violence to achieve a political end. An examination of past insurgencies reveals terrorism as a tactic to produce affects against the ruling government or the populace. Defining success in the war on terrorism requires an understanding of both the insurgent and terrorist operational environment in order to determine success criteria. Dr. Max G. Manwaring developed a theory on counterinsurgencies through an examination of 43 post World War II insurgencies. Manwaring's paradigm provides a model, which is applicable to measuring success in the war on terrorism. While the model is a useful tool for defining success, it requires a thorough understanding of the terrorist and insurgent operational environment. Through examination of two case studies, the Philippines, 1948-1954 and Colombia, 1966 to present, the research assessed the Manwaring paradigm. The comparison revealed the complex operational environment and suggested other relevant factors, not addressed by Dr. Manwaring, for defining success in the war on terrorism. Those factors a systems approach to analyzing insurgencies and terrorist organizations and consideration of political primacy in the use of military and interagency capabilities. There is a significant body of knowledge on insurgencies and terrorism that can be applied to combating terrorism. There is a pressing need for the institutional military to educate the force on insurgency and terrorism. Insurgent and terrorist organizations are complex adaptive systems, which require a holistic campaign plan to defeat. Introducing systems thinking into the military education system will provide planners with the conceptual framework to analyze and develop coherent operational plans to achieve the strategic objectives in the war on terrorism.