The more machine-guns were firing from different angles, the more difficult it was to locate any one of them by either method; and the more influential the human element. In the midst of their fire imagination easily multiplied the number of guns, which is one of the moral effects of their use. When a gun was located, the gunner might slip back behind the crest of a ridge, or he might have moved as a precaution, before he was located, to another position which had been chosen as his next berth, with pit and camouflage in readiness.
An experienced aviator—always there is that word "experience" which has no substitute—might detect a machine-gun nest if he flew low; but not as a rule in woods or in bushes, or even in the open when covered with green branches. There were many machine-gunners and relatively few aviators. If a gunner thought that an aviator who flew low had seen him, he might have taken up a new position before the aviator's information had brought down artillery fire. The machine-gunner was a will-of-the-wisp with a hornet's sting, which could be thrown a mile and a half. Usually the price of locating him was casualties to the infantry, and still more casualties before he was taken, if he stood his ground. If the Germans had not enough machine-guns back of their first line for a complete interlocking defense on the first day of the battle—and they certainly had later—they aimed to place them where they could do the most good.
Naturally the American Army, studying its chessboard, had taken into consideration the counter-moves of the enemy which would result from its attack. Of course the passage through the entanglements would lead to the first dislocations of liaison; the storming of the trenches to more; and the passage over the shell-craters to still more. After every offensive against the trench system, officers had studied how to avoid the slowing down of the attack after the first line was taken. This had led to passing the first wave promptly through the trenches and leaving a second wave to "mop up" by "breaching" dugouts and cleaning up points of resistance; and then to the system of "leap-frogging," in which, when the men in front had been weakened in numbers by casualties and lost their aggressive cohesion, fresh troops went through them to carry forward the attack. Reserves in passing through the lanes of the barbed wire and over the trenches and on to catch up with an advancing line also suffered from disorganization, which might be increased by strong concentrations of enemy shell and machine-gun fire.
A division commander had discretion as to how he would gain his objectives, which brings us into the field of tactical direction, as technical as it is vital to success. His dispositions were a test of his knowledge of his profession, and his handling of the division after it was engaged of his qualities of generalship. In some instances villages and strong points were passed by the main line of advance, and left to be conquered by special attacking forces. Instructions had not only to be elaborate but practical.
Those captains and lieutenants, the company and platoon commanders, who were carrying out the instructions, must each be a general in his own limited field. The less experience his seniors had in preparing practical instructions, the more he might suffer for his want of experience in leading men in battle. With the conquered trenches behind him, he had to make sure that his men were in hand, and if he had been allowed no time for reorganization behind his shield, that was an error; for barrages might move too fast, in expressing the desire of commanders for speed. At the same time, the line officer had to identify by the map the ground on his front which he was to traverse and the positions he was to take as his part in that twenty miles of pulsing, weaving, and thrusting line.
When you are seated before a table in calm surroundings, trying to follow the course of one company in an advance, you realize the limitations of your 1 to 20,000 map. It ought to be 1 to 10. More elements than any layman could imagine entered into the problem of the location of the command post from which a battalion commander was to direct the movements of one thousand men, or a regimental commander of three thousand, in action. All this, of course, represents sheer fundamentals in thoroughgoing military science; but we must have the fundamentals if we are to appreciate the accomplishment of our young army in the Meuse-Argonne battle.
A prominent hill was easily recognized. If a village were in the line of your attack, that was a simple guide; but in a region where, unlike our country of scattered farmhouses, the farmers all live in villages, there was a paucity of buildings which might serve as landmarks. One of our men expressed the character of the terrain by saying that with every advance it all looked alike—hills, ridges, woods, and ravines; yet when you came close to the part which you were to attack it seemed "different from any other and a lot worse." We had to cross brooks and swamps as an incident to conquering the other features of the landscape. If we missed any kind of fighting on the first day of the battle, it was in store for us in the later stages.
Oh, that word liaison! That linking up of the units of the attack in proper coördination! Is there any man of the combat divisions who does not know its meaning or who wants to hear it again? It never came into slang at home in the same way as camouflage; but it is a thousand times more suggestive of the actualities of war. Liaison between the French and the American armies, between corps, divisions, brigades, regiments, battalions, companies, platoons, squads, and individual soldiers. Liaison between infantry and artillery and trench mortars and planes and tanks! If you did not have it, why, the adjoining commander might be as much to blame as you, at least, and you could say that he was altogether to blame. It may be said that the history of the war will be written in terms of positions taken, and of positions which were not taken because coöperating units failed to keep their liaison. They were not up. When I mention that there were difficulties of liaison in writing of any division, I am not saying who was at fault, as no one person was, perhaps, more than another.
Other generals might be promoted and demoted, but General Liaison remained the supreme tactician. "Establishing liaison" was fraught with more heartaches and brain-aches than any other military detail. Men prowled through the night in gas-masks under sniping rifle and machine-gun fire and artillery fire, to ascertain if the unit supposed to be on their flank was there: perhaps to receive a greeting from an officer hugging a fox-hole, "Why aren't you fellows keeping up with us?"