Center of gravity (COG) is a military term that refers to the source of strength, balance, or stability necessary for a military force to maintain operation. Centers of gravity exist for all belligerents and at all tactical, strategic, and operational levels of war simultaneously. The concept was first developed by Carl von Clausewitz, a Prussian military theorist, in his work On War.
United States
The United States Department of Defense defines a COG as "the source of power that provides moral or physical strength, freedom of action, or will to act", although there has been a significant and widespread push to revert to a more classical, Clausewitzian interpretation of the phrase. There are twelve qualities of COGs the Joint Chiefs of Staff have doctrinally recognized:
Exists at each level of warfare
Mostly physical at operational and tactical levels
Is a source of leverage
Allows or enhances freedom of action
May be where the enemy’s force is most densely concentrated
Can endanger one’s own COGs
May be transitory in nature
Linked to objective(s) Dependent upon adversarial relationship Can shift over time or between phases Often depends on factors of time and space Contains many intangible elements at strategic level
The COG is the root enabler of the enemy's ability to interfere with friendly forces' mission, and vice versa. However, the various United States Armed Forces Service branches interpret this concept in different manners. Due to this size of the United States Army, it tends to recognize a COG as a combatant's strongest characteristic, capability, or locality. Conversely, the United States Marine Corps prefers to view a COG as the weakness of a combatant. For example, a counter-insurgency's COG may be defined as the entire host population, an external nation's support, or a core group of leaders/believers.
Center of Gravity Analysis
COG analysis helps to identify vulnerabilities and how an actor's will might be influenced to achieve objectives. Most modern systems of COG of analysis rely on the Joseph Strange's assessment framework of critical capabilities, critical requirements, and critical vulnerabilities. Critical capabilities are the primary abilities essential to the accomplishment of the mission. Critical requirements are essential conditions, resources, and means the COG requires to employ the critical capability. Critical vulnerabilities are aspects of critical requirements vulnerable to attack. The National Defense University (NDU) and Joint Forces Quarterly (JFQ) discuss three approaches to assessment of these critical factors:
Eikmeier method
Godzilla method
Critical Factors Analysis (CFA)
Both the Eikmeier and Godzilla methods provide testable criteria for measuring and assessing various factors in the analysis. Meanwhile, CFA uses a subjective system of "means, ways, and ends" to assess critical capabilities, critical requirements, and critical vulnerabilities.
Eikmeier Method
Identify the organization’s desired ends or objectives. Identify the possible “ways” or actions that can achieve the desired ends. Select the way(s) that the evidence suggests the organization is most likely to use. Remember: Ways are actions and should be expressed as verbs. Then select the most elemental or essential action—that selection is the critical capability. Ways = critical capabilities. List the organization’s means available or needed to execute the way/critical capability. Select the entity (noun) from the list of means that inherently possesses the critical capability to achieve the end. This selection is the center of gravity. It is the doer of the action that achieves the ends. From the remaining items on the means list, select those that are critical for execution of the critical capability. These are the critical requirements. Complete the process by identifying those critical requirements vulnerable to adversary actions.