The correct apportionment may also be influenced by any military changes to be effected in the characteristics of the theater (as indicated in the Principle of Proper Physical Conditions to be Established--page 34). Thus, the establishment of a well defended base may operate, properly, to reduce the requirements for apportionment of a force for a particular duty in that locality. Similarly, the proper use of fortifications, obstacles, demolitions, and routes by land, sea, and air, as well as facilities for exchange of information and orders, all operate to increase fighting strength relative to that of the enemy. The next consideration, that of feasibility, takes account of the type and of the amount of means that can be apportioned in view of the means available. In connection with the foregoing there will be appropriate requirements for the operation as a whole and for its component operations. All of these requirements may call for analysis of the relative positions to be utilized, with reference to the selected physical objectives, and of the requirements for adequate freedom of action. Finally, the requirement of acceptability as to the factor of consequences will call for consideration of the results of the allotments of forces to particular tasks. This is necessary in order to arrive at reasonable conclusions as to the military costs involved either in event of the success of the effort or in event of its failure, and with respect, more especially, to the effects on future action. The attainment of the objective, however suitable as to the effect desired, may be found, on the basis of due study, to be infeasible or to involve unacceptable consequences. The inescapable conclusion is then that an increase in relative fighting strength is required or that another objective, feasible of attainment and acceptable with respect to consequences, is necessarily to be adopted (see page 52-53). Freedom of Action Fundamental Considerations. In providing for proper apportionment of fighting strength, a commander may attain the end in view by increasing the physical, mental, or moral elements of his own strength, relative to the enemy's, or by decreasing the enemy's strength through imposing restrictions on hostile freedom of action. Freedom of action will enable a commander to prosecute his plan in spite of restrictive influences. That enemy interference will, to a greater or less extent, impose restrictions on freedom of action is to be expected. Restrictions may also be imposed by physical conditions existing in the theater of operations, and by deficiencies and omissions which are within the field of responsibility of the commander to correct.