FM 3-24.2 Tactics In Counterinsurgency dated April 2009 provides the following definition for an Insurgency, "This is an organized movement aimed at the overthrow of a constituted government through use of subversion and armed conflict. The key distinction between an insurgency and other movements is the decision to use violence to achieve political goals. An insurgency is typically an internal struggle within a state, not between states. It is normally a protracted political and military struggle designed to weaken the existing government’s power, control, and legitimacy, while increasing the insurgency’s power, control, and legitimacy." For those that want to better understand what an insurgency is they need to reference FM 3-24.2, which is the leading doctrinal reference for defining how insurgencies operate, how counterinsurgency (COIN) operations are conducted, and how to employ tactics to mitigate the operational environment necessary for an insurgency to thrive. FM 3-24.2 is a culmination of two centuries of counterinsurgency operations from the Whiskey Rebellion in the eastern United States, the Native Americans on the western plains of the United States, the Boxer Rebellion in China, Pancho Villa in Mexico, Augusto Sandino in Nicaragua, the Viet Cong in Vietnam and current counterinsurgency operations being conducted globally. This field manual also provides both the novice and the scholar the key information on how the following influences define today's operational environment which is creating the setting for insurgencies to be the standard warfare for the foreseeable future: population explosion, urbanization, globalization, technology, religious fundamentalism, resource demand, climate change and natural disasters, and proliferation of weapons of mass destruction. This field manual is a must for your personal library and can found for free on the Army's Publishing Agency website.