(iv) Information and counter-information measures. Operations of war are tremendously affected by the information which each belligerent possesses of the others. It is therefore of vital importance to weigh the efficiency of the belligerents in the employment of means of obtaining, denying, and utilizing information.
There may appropriately be considered present, probable, or possible use or non-use of indirect methods such as: study of press, captured documents, and material; reports from other friendly units; interrogation of prisoners of war, deserters, inhabitants, and escaped or exchanged prisoners; radio direction-finding; efficiency of cryptography; interception of enemy radio, telegraph, telephone, and mail communications; espionage; censorship; propaganda; efficiency of communications systems, ashore and afloat, which include all means of interchange of thought. In this connection it will be recalled that information, however accurate and appropriate, is useless if it cannot be conveyed in time.
The direct methods of obtaining information are military operations intended for that purpose, such as observation, reconnaissance, scouting, trailing.
Counter-information measures are no less important than those pertaining to collection of information. Such measures include all provisions for secrecy, such as censorship, counter-espionage, cryptography, control of own communications, security of documents, camouflage, and applicable tactical operations.
(b) Factors More Directly Applicable to Armed Forces, (i) Vessels, including aircraft. The numbers and characteristics, of the ships and aircraft of the various nations of the world are known with less and less accuracy from the time when war becomes a probability. The information available is given intense and comparative scrutiny, under the specific headings of the factors of the Estimate Form as later enumerated.
(ii) Land forces, including land-based aviation. Important facts concerning the land forces of the enemy, including his land-based aviation, will be known, probably, to a lesser extent than in the case of the naval forces. The value of a comparison—naval, land, or air—may depend upon whether the intelligence service has improved the accuracy of these data, maintained them up to date, and collected accurate additional information.
(iii) Personnel. The status of enemy personnel as to the sufficiency of numbers effectively to man all implements, as to training, morale, skill, stamina, and willingness to accept the supreme sacrifice, can seldom be accurately known. Unless there is positive information to the contrary, the wise commander will assume in this respect that the status of the personnel available to his opponent is at least equal to that of his own command. Full consideration will be given to all known facts concerning own personnel, to the end that its worth in any proposed situation may be properly evaluated.
The basic discussion of the psychological factors ([page 125]) is applicable here as to the respective armed forces. Personal characteristics of commanders, so far as known, deserve full study, since they have an important bearing on relative fighting strength. The military value of the various units and forces is a similar consideration. The present attitude and past actions of enemy commanders and of their commands, and the factor of racial, national, and service characteristics, may furnish clues for correct evaluation in this connection.
(iv) Material. The material characteristics of the commander's own implements of war are generally known to him. The characteristics of enemy material can only be estimated from such data as have become available, but are not to be underestimated.
Material characteristics embrace armament, life, and mobility.