1. INTRODUCTION

The information in this section summarizes the tactics used by the Japanese in and around Milne Bay, New Guinea. The terrain over which most of the operations took place consists, generally speaking, of a narrow coastal strip, varying from 1/4 mile or less to 1 mile in width. It is composed mainly of thick jungle and waist-deep sago-palm swamps, with occasional coconut plantations scattered about near the villages. This narrow strip is bounded on the inland side with a chain of hills and mountains, some of which rise to a height of 3,500 feet. Deep gorges cut this range at several points.

The Japanese attack was carefully planned to take advantage of the terrain, and of extremely heavy rains which were falling at the time.

2. SUMMARY BY OBSERVERS

In summing up the Japanese tactics, United Nations observers stated that the meeting engagement is the basis of Japanese combat training—their official regulations give more space to it than to any other form of combat. The Japanese believe that the meeting engagement provides for the best development of swift and decisive offensive action, and they deliberately seek it.

The meeting engagement offers the Japanese the added advantage of minimizing deficiencies in matériel—especially artillery—and in the support by combined arms. In addition, the Japanese feel that the meeting engagement will enable them: to seize and hold the initiative, to allow subordinate commanders to take bold and independent action, and to occupy important terrain features quickly.

Nearly all the Japanese tactics in the Milne Bay fighting were centered on attack. All defense positions were covered by a screen of snipers, who were difficult to dislodge. No Japanese maneuver is ever attempted without including some ruse to deceive the opposition and to conceal the true intentions of the commander.

3. PATROLS

The size of Japanese night patrols encountered by our forces varied from 18 upwards, while day patrols averaged from 6 to 10 men.

As a rule, these patrols moved as a body and kept on or close to roads or trails. For reconnaissance, the Japanese did not employ fighting patrols, but used scouts, who worked singly or in pairs. These scouts utilized the thick jungle to approach our defended localities or were left in hidden positions when the enemy withdrew from a night attack. The scouts lay very still while close to our troops and allowed our patrols and working parties to pass unmolested.

4. NIGHT OPERATIONS

The Japanese relied almost entirely upon night operations for which they appeared to be well trained.

a. Approach March

During the approach march, the Japanese moved rapidly, in groups of 20 to 30 and with little regard for flank protection. The main line of advance was the road or beach, and no organized groups or units appeared to have moved more than 300 yards from the road. If the Japanese had tried to secure their flanks, their speed of movement would have been cut down considerably. They talked a great deal during the approach, but were careful about lights. While assembling, and just before the attack, they maintained absolute silence. However, they had a tendency to bunch up while assembling.

b. The Attack

Once the attack began, the Japanese made a great deal of noise, by firing mortars, grenades, and firecrackers, and by calling and whistling. These noises were made to draw our fire and demoralize our troops—and to boost their own morale at the same time.

The night attacks were made on a small frontage, but their mortars were fired well forward and to the flanks to give the impression of a large force advancing on a wide front. The rear elements appeared to be more widely deployed, for a probable flank envelopment.

When our troops opened fire, the Japanese tried to infiltrate around our flanks and to our rear. After assembling and taking up positions, these enemy troops attempted to rush our posts under the cover of mortar and grenade fire.

c. Withdrawals

The night attacks were suddenly broken off before daybreak. Chattering as they went, the Japanese withdrew along the road except for snipers and observers, who were left in trees close to our forward defense lines and along trails. A great deal of equipment was abandoned, but no wounded were left.

d. Use of Tanks

The Japanese used at least two light tanks, which had strong headlights. Some machine gunners rode on top of the tanks or followed close behind. Other infantry parties preceded the tanks in defiles, such as ravines or gullies, for the purpose of attacking our antitank guns.