By January 1943 all Army and Marine Corps units which were to take part in the campaign had landed and been committed to action. From hard experience the Americans had learned a great deal about jungle fighting, acquiring a knowledge which was to be advantageous to the forces which were to take part in the final offensive, as well as in later campaigns in the Pacific. The lessons of the Guadalcanal campaign, ably compiled by the men who fought there, reflect in concrete terms the nature of the fighting described above, as well as that which was still to come.
The Americans: Tactics
Thus far the fighting on Guadalcanal was clearly showing that the offensive and defensive principles embodied in the American tactical manuals were basically sound and sufficiently flexible to be adapted to the terrain in the Solomon’s. The Americal Division, in its operations on the beach, advocated advancing on a broad front with units in column and echeloned to protect the flanks. Because the rough terrain and thick jungles prevented commanders from exercising close control over widely dispersed units, the columns deployed as late and as close to the enemy as possible.
The 25th Division, which operated over open hills and jungle country, found that squad columns and skirmish lines could operate effectively over open ground. For approach marches in deep jungles, where an entire battalion often moved over a single trail, a column of files, deploying as late as possible, was best. All divisions and regiments agreed that the wisdom of enveloping one or more of the enemy’s flanks, rather than attacking frontally, had been repeatedly demonstrated. When the Japanese resisted vigorously from a pocket or strong point, the best technique was to bypass the pocket, continue the advance, and reduce the pocket at leisure.
Except in rare instances, advancing units usually halted early enough in the afternoon to establish all-round defenses and permit defensive artillery and mortar concentrations to be registered before the fall of darkness. Halting in the afternoon gave the troops time to dig foxholes and emplacements, string barbed wire, emplace and site heavy weapons, and camouflage the position as much as possible. By halting in daylight, troops in the jungle could also determine the location of the units on their flanks. If this was not done, inexperienced troops were apt to fire on each other during the night. All movement within a defensive area ceased after nightfall.
Infantry fighting was close work, as most targets lay less than fifty yards from the infantrymen. The nature of the terrain broke most engagements into “small unit scraps” in which “success is dependent upon the individual soldiers, NCO’s, and platoon leaders’ ability to act promptly and intelligently when confronted with a situation.”
The soldiers and marines had seen repeatedly demonstrated the obvious truth that success in war demands skillful and vigorous leadership from all ranks charged with the responsibility of providing leadership. Those whose leadership faltered under the stress of combat had to be relieved of their commands.
American weapons had generally proved to be both potent and practical. The U. S. Rifle, M1 (Garand) had shown itself to be superior to the M1903 (Springfield), with which many marines had been armed. Other small arms were less satisfactory. The .45-caliber automatic pistol found little use. The Marines’ Reising Gun, a .45-caliber submachine gun, proved to be almost worthless. The .45-caliber Thompson submachine gun, while efficient, sounded too much like Japanese .25-caliber weapons, and could not be safely employed at the front. Bayonets and knives were valuable in close combat at night, as were hand grenades, but rifle and antitank grenades lacked sufficiently sensitive fuzes.
The larger infantry weapons were extremely efficient, although most troops complained of their weight. The light air-cooled .30-caliber machine gun supplanted the heavy water-cooled .30-caliber machine gun in supporting infantry attacks, but the most valuable infantry weapon for an attack was the light, mobile .30-caliber Browning automatic rifle. Caliber .50 machine guns and 37-mm. antitank guns, while not generally used offensively, were excellent in defense positions, as were the heavy .30-caliber machine guns. The 60-mm. mortar, carried by hand, followed closely behind assaulting infantrymen, and its fire was effective in open terrain. The 81-mm. mortar could not follow closely behind an attack, but it was usually brought forward as soon as possible and was invaluable for close support of the infantry.
American troops, in accordance with standard tactical doctrines, were relying heavily upon artillery for both offense and defense despite inaccurate maps, limited observation, and the difficulties of hauling ammunition. Of the three calibers of howitzers generally used on Guadalcanal, the 75-mm. pack howitzer, though mobile, was too light; the 105-mm. howitzer was very good, and the 155-mm. howitzer was excellent. Neither the XIV Corps nor the divisions possessed any organic aviation, and adjustment of the artillery was usually effected through forward observers. Since infantrymen in their first battle were often apprehensive when their own artillery put fire over their heads to hit targets directly in front of them, forward observers usually laid the first registration shots deep in enemy territory, and then brought the fire back toward the American front lines.
Close support of ground troops by aircraft, used consistently by the 1st Marine Division, was being continued by the XIV Corps. Close air support was not always easy to employ, for complete radio facilities for air-to-ground communications were not always available, and the designation of the enemy targets and American front lines by panels and smoke was not always accurate in rough terrain. The best solution for these difficulties lay in careful planning, close liaison, and direct observation of the targets and front lines by the pilots before taking off.
Tank destroyers, in support of the infantry, were effective in defensive missions, and where there was space for maneuver they were useful offensively. Tanks were very good in the offensive but the jungle, by hampering their fields of vision and freedom to maneuver, limited their effectiveness by making them easy prey to mines and antitank guns. They were safe only when closely supported by infantrymen. Light tanks, the only kind employed on Guadalcanal, were vulnerable to enemy gunfire; medium tanks would have been better.
In addition to the information it received from coastwatchers and higher headquarters, the XIV Corps, like the 1st Marine Division, was deriving knowledge of enemy strength, dispositions, and capabilities from all the units under its control. Motor torpedo boats, patrolling Sealark Channel and the coasts of the adjacent islands, reported regularly. Direct aerial observation and aerial photographs yielded valuable data. Corps headquarters, though hampered by lack of enough photographic interpreters, based its plan of attack in January largely upon conclusions derived from the study of photographs. The Corps depended on ground patrols, usually of reinforced platoon strength, for close-in combat intelligence—finding routes of approach, enemy front lines, soft spots, and strong points. The quality of patrolling had been improving since D Day. Reconnaissance patrols had learned to avoid battle but to gather information, and the men had become more confident of their ability to move and fight in the jungle. But until the end of the campaign reports from ground patrols were often erroneous. Misled by the difficulty of walking through dark, rough jungle, patrols frequently overestimated the distances they had traveled.
Captured documents were still a fruitful source of data on enemy units, for the Japanese carelessly carried diaries and orders into the front lines. Prisoners of war, if well treated, usually gave voluminous testimony on all subjects. Apparently the Japanese belief that it is dishonorable to surrender had led the Imperial Army to neglect to instruct soldiers on what to do if captured, for the enemy soldiers, once taken prisoner, talked freely. But very few Japanese soldiers ever gave themselves up voluntarily. The American troops, who were fearful of the widely publicized treacherousness of the enemy, were reluctant to take prisoners, and the Japanese soldiery usually fought until they were killed rather than capitulate.
The XIV Corps, besides the voice broadcasts at the Gifu, also employed leaflets to induce surrenders. On 10 January Allied planes dropped 18,000 copies of a War Department propaganda leaflet which compared the hardships of the front-line soldier with the ease of those behind the lines. Two days later 25,000 copies of Emperor Hirohito’s poem on peace were dropped. The War Department had also furnished a surrender leaflet, but because it urged the Japanese to surrender at any time, it was altered. In the revised version the Japanese were instructed to surrender by entering the American lines through open areas in daylight, unarmed, their hands above their heads. These leaflets were dropped on 16 January. Their effectiveness is difficult to measure. Out of a group of eighty-four prisoners taken by the XIV Corps between 1 January and 15 February 1943, thirty-three were sick or wounded men who could not walk. Fifty-one gave up voluntarily, and only twelve of these had surrender leaflets in their possession.
The Measure of the Enemy
American troops, none of whom had received the specialized jungle training that was later given to all units in the Pacific, were learning that the Japanese though “a brave, resolute, and often skillful soldier, could be soundly beaten. On the offensive his endurance, high morale, and soldierly ability made him dangerous.” Yet there were grave weaknesses inherent in Japanese offensive tactics. His artillery was seldom present in sufficient strength, by American standards, to support an offensive, and his artillery techniques were not sufficiently developed to mass fire and change targets quickly. Although fairly efficient in night operations, the Japanese often ignored the dangers of assembling in or marching through areas on which American artillery fire had already been registered. The maneuver employed in the October counteroffensive—an attack against an axis of communication, coupled with an envelopment through “impassable” terrain culminating in a mass rush on a narrow front—employed dense concentrations of infantrymen, which were vulnerable targets for both artillery and infantry fires.
The Japanese, in an offensive, was wont to follow a fixed plan rigidly; he apparently lacked either the flexibility of mind or enough military technique to alter his plans when they went askew. The Japanese, on the other hand, believed that American troops lacked initiative, that they would execute a given order and then stop rather than exploit their opportunities to move forward.
Japanese military judgment appeared to err on the side of optimism, for in offensive action on Guadalcanal the enemy almost invariably committed forces smaller than those of the Americans. His intelligence techniques were apparently unsound; he consistently underestimated the size of the forces opposing him. However, the Japanese had learned caution in one respect. Although continuing to stress infiltration and harassment, he had learned that American flanks and rear areas were not as vulnerable as he had once believed.
In defense the Japanese soldier was more skillful, and hence more formidable, than in offense. His strong points were well located and well organized, his weapons well sited, and his camouflage superior. His tenacity, his willingness to starve or be shot rather than surrender, may be denounced as fanaticism, but such qualities gave vital strength to his defense. His weapons—.25-caliber rifles, mortars, grenade dischargers, and artillery—were well made and efficient although his technical proficiency in the use of weapons was lower than that of the Americans.
The Japanese was also learning much about American troops and methods, although he does not always appear to have applied his lessons in the Solomon’s campaigns. In general, he was impressed by American equipment and fire power. He admired the mechanized equipment and the abundance of ammunition, although claiming that many of the artillery shells fired on Guadalcanal failed to explode. He particularly admired the skill of American artillerymen in massing and shifting fire. While denying that American tactics were better than Japanese, he noted that the former, though somewhat cautious, were thorough, well planned, systematic, and sound. Co-operation between the Army and Navy, he believed, was good. He considered that American troops, though unduly prudent and apt to fire too high, were steady in the attack.9 In the words of the 17th Army’s former chief of staff: “As a former soldier I must pay respect to the American infantrymen, artillerymen, and tank corpsmen who attacked the Japanese Army sustaining severe losses in each battle, while suffering the hardships of malaria and amoebic dysentery in the Guadalcanal and New Guinea campaigns.”
On the best motor roads of Guadalcanal, trucks could travel at twenty miles per hour if the roads were not muddy. Off the roads, they could scarcely move. On the jungle trails, the average march speed for troops was one mile per hour. Off the trails in the jungle, where troops had to hack their way through the undergrowth with machetes and bayonets, a half mile per hour was a rapid march speed. Under these conditions, supply and evacuation posed grave problems. Supply dumps were located as far forward as possible, and trucks carried supplies from the dumps to the termini of the roads. From the road-end forward, supplies were carried by hand, by boat, and by cableways. In the front lines, where men were forced to remain under cover, supplies were usually distributed by being thrown from foxhole to foxhole.
There were never enough trucks, but those which were available were giving excellent service. The powered front axles of American military trucks enabled them to traverse bogs, mud, and sand which would have stopped ordinary vehicles. The 2½-ton truck, although not always sufficiently powerful to pull a 105-mm. howitzer, worked well, as did the jeep.
One interesting experiment in transportation in jungle warfare was the use of mules. The 97th Field Artillery Battalion (75-mm. pack howitzers) which supported the advance up the north coast had mules. The presence of the animals complicated rather than simplified the logistical problem. Mules could not traverse all the types of terrain that a man on foot could negotiate. They could not get over boggy ground or cross muddy banks and stream beds. Although able to cover from four to five miles per hour over favorable terrain, the mules could cover only one mile per hour over Guadalcanal’s roads and trails. As a result they caused traffic jams and impeded the trucks. Nor could the battalion easily supply itself. Each firing battery had 193 men and 117 mules. This entire strength was required to transport the four 75-mm. pack howitzers and 200 rounds of ammunition allotted to each battery. To assist in moving ammunition forward, one ammunition section from the Service Battery—including 43 pack mules and 23 riding mules—was attached to the firing battery, to increase its strength to 212 men and 182 mules. But each mule required eight pounds of oats and 14 pounds of hay per day for feed. Thus, keeping four guns in action required the services of 212 men and 182 mules. To feed the mules necessitated hauling 1,500 pounds of oats and 2,600 pounds of hay to the front daily by some agency other than the firing battery, for the mules could not haul feed as well as howitzers and ammunition. The experiment was unsuccessful. Evacuation of the wounded was effected by the same general means by which supplies were brought forward. Cableways, hand-borne litters, jeeps, boats, ambulances, and trucks were all employed.
Engineering problems, like all others on the island, were difficult to solve. Roads through the jungle and over the steep hills were hard to build and maintain. Since the XIV Corps possessed no corps engineers, Americal and 25th Division engineer battalions functioned as both corps and divisional engineers. Each battalion had been able to transport only two bulldozers to Guadalcanal, and the bulldozers were too old and too light for efficient service. Not until January was there a power shovel for the Army engineers, and at no time was there a sawmill. Since flash floods on the rivers usually washed out temporary bridges, the 1st (Marine) Engineer Battalion in November ingeniously built its own pile driver with salvaged steel trusses, a ¾-inch steel cable, a gasoline-driven winch, and a 500-pound hammer. This contrivance, which could drive 8-inch piles from eight to ten feet into the river bottoms, enabled the marines to build bridges that would withstand the floods.
Rations and Clothing
The rations usually served to troops in combat were the C and K rations. These were nutritious but somewhat greasy for use in the tropics. The C ration consisted of prepared meals—meat and beans, stew, or meat and vegetable hash in the dinner ration, and biscuits, candy, and a concentrated beverage powder for breakfast—packed in tin cans. One day’s ration weighed over five pounds, and was bulky and heavy in a man’s pack. The concentrated nonperishable K ration included a small can of cheese or meat paste, biscuits, candy, beverage powder, chewing gum, and two cigarettes. It was packed in waterproof paper packages, was lighter than the C and easier to pack. But most men found the cold K rations tiresome, and agreed that the C ration, whether hot or cold, was wearisome.
Men did not carry complete mess kits into action with them. A canteen cup and spoon sufficed each man. Both C and K rations could be eaten out of the containers with either hands or spoon. Means of washing mess kits thoroughly were not to be found at the front, and to eat from an improperly washed kit led to violent diarrhea.
In the rear areas, when kitchens and messes were established, hot meals were served. But they were little better than those at the front, for they were prepared from canned and dehydrated meats and vegetables. There were virtually no fresh foods—eggs, milk, butter, or meat—then available on Guadalcanal, and shipping and refrigerator space was too scarce to ship such commodities for anyone but hospital patients. The only fresh food most men tasted during the campaign came from a shipment of turkey, fresh potatoes, oranges, and celery brought in for their Christmas dinner.
For combat in the jungle, the light color of the cotton khaki uniform was too conspicuous. The uniform most suitable for combat was, for the soldier, the two piece green twill fatigue uniform rather than the one-piece coverall, and for the marine, the two-piece green utility suit. Shoes made of undressed leather, well covered with waterproofing grease and soled with rubber or a composition material, rendered the best service. Canvas leggings did not give good service. They held the damp and chafed the ankles, and the buckles, straps, and hooks caught in the underbrush. The steel helmet was invaluable; besides protecting the head it served as an entrenching tool, cooking pot, and wash basin.
Voice radio sets were not functioning at full efficiency on Guadalcanal. Moisture and corrosion affected the circuits and metallic contacts, altered frequencies, and occasionally drowned out sets completely. The heavy jungle and deep valleys blocked the waves from some of the lighter sets. Some sets assigned to the infantry divisions were too heavy to move conveniently by manpower when trucks and roads were not available. The SCR’s 194 and 195 (the “Walkie Talkie”), powered by dry batteries, possessed a range of from one to two miles. They served well enough in open and high ground, but were ineffective in the jungle. The battery-powered 6-pound SCR 536 (“Handy Talkie”), with a range of 1½ miles, could be used only in open terrain and was very fragile.
The 20-pound battery-powered SCR 511, with a range of five miles, was dependable if kept dry, and could readily be carried by one man. The most reliable set for infantry use was the portable, hand-generated SCR 284. This set, with a range of seven miles, weighed no pounds, and required several men to carry it. The SCR 284 could be transported in a jeep, but jolting over the rough roads was apt to damage it. The bulky, long-range SCR 193 proved to be effective for ground-to-air communications, as well as for communication between division and corps headquarters.
In the absence of reliable radio communications the infantry regiments, battalions, and companies were relying most heavily on wire communications. They employed the EE-8 field and the sound-powered telephones for long and short distances, respectively. Wire communications, though reliable, required continuous maintenance. Wires had to be strung overhead for complete efficiency, since vehicles and men on foot were apt to break wire laid on the ground. One of the most effective circuits for field telephones was a ground return circuit superimposed upon a metallic circuit by the use of repeating coils. Ground return circuits gave more reliable service than completely metallic circuits, but were subject to interception by the Japanese.
The lessons of the first months of Guadalcanal had been well learned, were applied in the final stages of the campaign, and were to be embodied in future training programs. Training for jungle combat would need to be realistic and rigorous; it would need to employ difficult, extended maneuvers over long and arduous distances, intensive practice in scouting and patrolling, experience in undergoing overhead fire, close infantry-artillery teamwork, and wide envelopments, as well as thorough training in the use of weapons.
The morale and mental attitude of the troops had been and would continue to be an integral part of their preparation for combat. The exaggerated reputation which the Japanese righting man enjoyed during the early part of 1942 had by now been deflated, but a few superstitions remained in men’s minds. One of the great bugaboos of the Guadalcanal campaign which slowed nearly all advances by the infantry was the belief, firmly held by nearly all troops, that Japanese “snipers” operated from treetops. But this belief, which the Japanese curiously entertained about American “snipers,” was seldom supported by facts. The Japanese rifleman was not especially equipped for sniping, nor did he usually climb into trees to shoot.
Realistic training would also be needed to accustom troops to battle and jungle noises, for the average American unit, during its first night in the jungle on Guadalcanal, would nervously fire at the sounds made by birds, land crabs, creaking branches, and falling foliage. Rigid discipline and training in sanitation were likewise necessary. It was essential that soldiers be thoroughly indoctrinated in the need for disposal of all waste materials, and that malaria discipline, including the use of mosquito nets, complete clothing after dusk, killing of mosquito larvae, and the regular use of atabrine tablets, be strictly enforced.
Source: Guadalcanal: The First Offensive ; BY: John Miller, Jr. (United States Army Center of Military History)