force will find itself literally in a state of siege under the worst possible conditions, for the position will be one in the form of an extended line along which the forces of all arms will be definitely immobilised, for the lateral communications will suffer no less than the lines from the rear. Such a position of affairs presents all the elements conducive to complete and irreparable disaster.
Thus, in the extended employment of aircraft, we have the means at hand of compelling a bloodless victory; for, once admit the truth of the present conclusions, the serious and comprehensive threatening of the communications of the enemy by aircraft on the lines indicated can only be answered by his retirement. If he neglects to take this step until too late, he pays the penalty in annihilation or surrender; the matter thus stated becomes one involving the ordinary logic of military necessity.
The magnitude of the aeronautical forces and establishment necessary to effect the present purpose must not be under-estimated. In order to prove a decisive factor the devastated zone will need to be of very great area, a belt of from 50 to 100 miles in width probably represents the minimum, and the destruction wrought over the said zone must be complete and thorough in every important respect. The accomplishment, however, is commensurate with the magnitude of the means, for an operation on the scale stated must be met by the enemy by a withdrawal of corresponding magnitude; no ordinary retreat of a few miles to a second line of defence can avail him. From the time his aircraft and air defences are overpowered and his communications placed in jeopardy, he must prepare to fall back on new lines established beyond the zone of devastation, that is to say, if the work is effectively done his retirement can be but little short of 50 or 100 miles. In the present war, this would mean virtually the evacuation and abandonment of the
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