Following the combat plan after the 1968 Tet Offensive, we initiated several offensive campaigns in crucial areas, including the Long Khanh Campaign. Though this campaign was small in scale, it showcased the flexible and creative application of ambush techniques, meticulously integrated with other tactical forms, resulting in continuous assaults and resounding victories. These efforts significantly contributed to defeating the “rapid pacification” strategy, forcing the enemy into a strategically passive position.

After suffering heavy losses in 1968, at the beginning of 1969, the enemy intensified the implementation of the “search and hold” strategy, modernised their military, reinforced the Saigon puppet government, and expedited “rapid pacification” to expand their control zones. They aimed to push liberation forces out of border areas, striving to strengthen the Saigon puppet army to gradually replace American troops. Their plan was to transform Long Khanh into a robust defensive line for the Long Binh - Bien Hoa military complex in the East and simultaneously create a distant “hard shell” for Saigon - Gia Dinh. They also focused on building security forces, militia, and police. The enemy positioned the 18^th Infantry Division (the main force of the Saigon puppet army) in Xuan Loc and other strategic locations along crucial routes and was ready to deploy American troops, the mobile forces of Tactical Zone III, and the strategic reserve forces in case of our attacks.

On our side, considering the battlefield situation and the assigned tasks, in early May 1969, the Command of the Southern Region decided to launch an offensive campaign towards Long Khanh. The objectives were to eliminate significant enemy forces, disrupt the “rapid pacification” plan, and thwart the “search and hold” strategy in the Southeast battlefield. By flexibly and creatively employing ambush techniques, effectively combining various tactical forms, timely creating and transforming the battlefield, and closely coordinating between “two forces, three types of troops,” we continuously assaulted, quickly dismantling the enemy’s formations and forcing them into a strategically passive state. The victory of the Long Khanh Campaign provided numerous valuable lessons in small-scale operational art, notably the distinct and exemplary ambush techniques demonstrated in several key aspects.

Firstly, to maintain close surveillance on the enemy and prepare for combat urgently. In the Long Khanh Campaign, our primary adversaries during ambushes were enemy forces temporarily halted during their mobile assault and airborne landings but unable to mobilise for counterattacks or relief operations. Consequently, the enemy’s state was in constant flux, highly volatile, and they often relocated their encampments overnight to evade our ambushes. To make precise combat decisions within a short timeframe while maintaining secrecy and surprise, and to engage at the optimal moment with high combat efficiency, it was imperative to closely monitor and grasp the enemy’s situation and prepare for combat with utmost urgency. The Campaign Command employed a range of flexible measures, effectively utilising various forces to conduct reconnaissance and thoroughly understand the enemy’s movements, especially those of the enemy forces in each ambush. This ensured accurate, specific, and meticulous preparation. In addition to leveraging intelligence provided by higher command, we maximised the role of the Campaign’s reconnaissance forces, particularly the 5^th Infantry Division’s reconnaissance units, which were in direct contact with the enemy. This was complemented by local reconnaissance forces in the operational area. By continuously tracking and accurately assessing the enemy’s situation, we detected early in the first phase of the campaign the intention of the 43^rd Regiment of the Saigon puppet army to return to support the defensive forces in Xuan Loc, which had been ambushed by our 29^th Regiment, leaving only the 11^th Airborne Battalion to wait for the 48^th Regiment’s forces to join the attack. Recognising this as a favourable opportunity, the Campaign Command promptly deployed the 23^rd Regiment to prepare for combat and unexpectedly ambushed and annihilated the 11^th Airborne Battalion, thereby disrupting the enemy’s consolidation plan. Similarly, understanding that the 4^th Battalion of the 43^rd Regiment was moving towards the Suoi Ret area (northwest of Xuan Loc), the Campaign Command directed the 29^th Regiment to swiftly manoeuvre from the south of Gia Huynh stream, prepare for combat rapidly, secretly approach, and seize the opportunity to ambush the enemy during the night. This resulted in the complete destruction of two companies of the 4^th Battalion as they temporarily halted south of Suoi Ret, achieving high combat efficiency. Thus, by continuously monitoring and accurately understanding every movement of the enemy and preparing for combat quickly, we maintained the initiative in our attacks. We consistently ambushed the temporarily halted enemy formations, annihilated enemy battalions, minimised casualties, and effectively disrupted the enemy’s “search and hold” operations, thereby continuously forcing them into a reactive and defensive stance.

Secondly, to accurately select ambush targets to quickly disrupt the enemy’s formations and achieve high combat efficiency. During the Long Khanh Campaign, to deliver decisive, impactful blows and annihilate individual enemy units, while implementing the strategy of organising small to medium-scale battles based on infantry regiments using the “encircle the position, destroy the reinforcement” tactic, the Campaign Command focused on precisely selecting ambush targets to ensure success and rapidly disrupt the enemy’s formations. Based on a thorough understanding, assessment, and accurate conclusions regarding the enemy’s situation, our own forces, the terrain, and the weather in the operational area, the Campaign Command selected enemy targets along Route 20; the American 3^rd Air Cavalry Brigade landing in Nui Dat, south of Ben Sau; and the enemy temporarily stationed at Tra Tan 3 and Dang Ca hill for continuous ambush and annihilation. These were precisely chosen targets, reflecting the keen, creative vision and thinking of the Campaign Command. These were enemy forces temporarily halted during mobile assaults or airborne landings, but not yet able to mobilise for relief or counterattacks. Their positions were unstable, with weak defences, incomplete fortifications, and minimal obstacles; their command and coordination revealed many vulnerabilities. Ambushing these targets would ensure victory, minimise our casualties, and achieve high combat efficiency. Moreover, by choosing these targets, we could completely annihilate individual enemy battalions, particularly units of the American 3^rd Air Cavalry Brigade, inflicting severe damage and contributing to undermining their invasion resolve. Additionally, these targets were located in critical areas (along Highway 20 and the intersection of Route 767 and Route 1). If these positions were eliminated, the enemy would continuously send reinforcements, providing us with opportunities to concentrate our forces and resources to annihilate large enemy forces outside their fortifications, pushing them deeper into a reactive stance. In practice, the 23^rd Infantry Regiment selected an American air cavalry battalion that had just landed south of Ben Sau for an ambush. They quickly completed all preparatory work, secretly manoeuvred their forces close to the enemy positions, formed multiple attack directions, simultaneously opened fire, surrounded, divided, and penetrated deep to eliminate the primary target. This caused the enemy to be completely reactive, surprised, and in disarray, with weak resistance, allowing us to systematically destroy each part and ultimately annihilate the entire enemy force.

In close coordination with the main assault, we proactively selected key targets, ambushing weak and vulnerable spots deep within the enemy’s rear, disrupting their command, and breaking their coordination and offensive formations. Following this strategy, the 29^th Regiment ambushed the rear of the enemy’s 18^th Division in Xuan Loc; using artillery and mortars to attack the headquarters of the 25^th Combat Group of the Saigon puppet army north of Chua Chan mountain, creating surprise and inflicting heavy damage. This forced the enemy to dispatch forces from other areas to provide relief, causing their forces to be dispersed across various directions, thus breaking their “search and hold” operations in key areas.

Finally, to flexibly and creatively apply ambush methods to control and exit the battlefield safely. In the Long Khanh Campaign, the Campaign Command directed units, especially those directly engaged in the attack, to flexibly and creatively apply ambush methods based on the enemy’s situation and specific terrain. These methods included surprise attacks (without prior artillery preparation) and assault attacks (with prior artillery preparation), delivering critical blows to the enemy. By closely monitoring and understanding the enemy’s state, the 23^rd Regiment’s ambush at Dinh Quan and the 29^th Regiment’s ambush on the rear of the 18^th Division of the puppet army employed the assault method. These were positions with relatively tight enemy defences, making it difficult to approach their positions secretly from the start. Consequently, after unexpectedly using 60mm and 82mm mortars to intensely and continuously bombard the enemy formations, the infantry units quickly surrounded, divided, and boldly penetrated deep to eliminate the primary targets from the outset, breaking the enemy’s formations, and systematically annihilating them to achieve victory. Alongside the effective use of assault methods, in the 174^th Regiment’s ambush at Ben Sau and the 21^st Regiment’s ambush at Tra Tan 3, recognising that the enemy had just moved in and temporarily halted without stabilising their formations, and exposed many vulnerabilities, we decided to use surprise attack methods. This involved secretly manoeuvring our forces, approaching, probing, removing obstacles, deploying formations right within the enemy positions, and suddenly launching a coordinated attack from both inside and outside, swiftly annihilating the enemy and achieving high combat efficiency.

A distinctive feature of ambush tactics is “strike fast, withdraw fast.” If we did not quickly control and exit the battlefield safely, the enemy could recover, use airpower and artillery for counterattacks, or deploy large infantry forces for retaliation. This would not only reduce the effectiveness of the battle and increase our casualties but also diminish the “surprise and unpredictability” that terrified the enemy. Therefore, in the Long Khanh Campaign, all our ambushes ended at the right moment, with controlled and organised withdrawals from the battlefield, minimising casualties. A notable example is the ambush of the American air cavalry battalion that had just landed south of Ben Sau (in the second phase of the Campaign). The 23^rd Infantry Regiment quickly controlled the battlefield, hunted down the remaining enemy soldiers, collected spoils of war, and organised a rapid, orderly, and safe withdrawal according to plan. This avoided the enemy’s air and artillery bombardments, preserved our forces, and prepared for subsequent battles.

The success of the Long Khanh Campaign thwarted the enemy’s “search and hold” strategy, dealt a severe blow to their “Vietnamisation” scheme, and forced the enemy into a strategically passive position. The valuable lessons on ambush artistry derived from the Campaign remain relevant and should continue to be studied and creatively applied to the cause of national defence today.

Colonel, Dr. PHAM QUANG TAO, Artillery College