Communications
In the military the term CCC (or "C3") is sometimes used to include "communications" as the "third C": Command, Control and Communications . Since military situations involve disrupted, hurried, confused or deliberately intercepted and altered communications - see signals warfare and information warfare, and also a degree of manipulation of emotion - see psychological warfare - it is important that communications be closely monitored to ensure that command actually results in control. Possibly the most extensive studies of this were in the Cold War when both the USA and USSR put great effort into ensuring that their strategic missile forces were under full control and that communications to them could not be interfered with, disrupted, or manipulated in any way.
Read more about this topic: Command Hierarchy