A truer definition is: "The area, whether of sea or land or both, within which the enemy must be overpowered before we can secure the object of the particular operation." Consequently, since the nature of the war varies with the object, it may be defensive in one theatre of operations and offensive in another. Where the operations are defensive in character any special movement or movements may be offensive. As the plan of war determines the theatres of operation in the theatre of war, so in each theatre of operation it determines the _lines of operation_ and the _objectives_. _Objective_ An objective is "any point or force against which an offensive movement is directed." Thus, where the _object_ in any theatre of operation is to get command of a certain sea in which the enemy maintains a fleet, that fleet will usually be the _objective_. "Objective" in ordinary use is frequently confused with "object." For purposes of strategical discussion it is desirable to keep them sharply distinguished. _Objective_ is the end of some particular movement or operation, and is the special concern of the officer in command. _Object_ is the end of a system of operations and is the special concern of the general staff or director of the war. An _objective_ is some definite point which we wish to get from the enemy or prevent his occupying, or some part of his strength which we wish to destroy. It is incorrect to use the term of anything we already possess. Thus, Vladivostock is often said to have been Rojesvensky's _objective_. It was, strictly speaking, only his _destination_. To reach it and concentrate with the units already there was the _primary object_ of the operations entrusted to him. He had no true _objective_ before him except Togo's fleet. An _objective_ is always subordinate to some _object_. It is a step to the attainment of that object. _Lines of Operation_ A line of operation is "the area of land or sea through which we operate from our base or starting point to reach our objectives." Lines of operation may be _exterior_ or _interior_. We are said to hold the _interior_ lines when we hold such a position, in regard to a theatre of operations, that we can reach its chief objective points, or forces, more quickly than the enemy can move to their defence or assistance. Such a position is called an _interior position_. "Exterior Lines" and "Exterior Positions" are the converse of these. _Lines of Communication_ This expression is used of three different things:-- (1) _Lines of supply_, running from the base of operations to the point which the operating force has reached. (2) _Lines of lateral communication_ by which several forces engaged in one theatre of operations can communicate with each other and move to each other's support. (3) _Lines of retreat_, which are usually lines of supply reversed, _i.e._, leading back to the base.