Implementing the Politburo’s strategic determination to liberate the South, on 5 March 1975, the Central Military Commission and the General Command decided to launch the Tri – Thien campaign with a view to attacking and destroying the enemy’s positions in the Tri – Thien defense line; coordinating with the main battlefield of Southern Central Highland and getting ready for advancement when the opportunity arises. The Tri – Thien Campaign ended victoriously leaving us with a number of lessons on distinctive military arts, including the seizing of opportunity, acting recklessly and opportunely.

Vietnam's liberation troops entering Hue citadel (file photo)

1. Actively deploying forces, establishing disposition and getting ready for big opportunity.

In accordance with the Paris Peace Accord (27 January 1973) the US had to withdraw their troops. This created us favourability in terms of status and strength and marked the big opportunity for a complete victory of our national salvation war against the US aggressors. Thoroughly appreciating all aspects, especially the strength balance between the enemy’s and our forces, the Party military committee and the High Command of the Tri – Thien military zone and the 2 Corps coordinated, and agreed to make combat plan for the Tri – Thien campaign. Accordingly, the three kinds of forces of the Tri – Thien military zone and 2 Corps would involve in the campaign. When the time came, they would seize the opportunity to facilitate offensive attacks, annihilate a significant part of the enemy and break down their pacification plan in Tri – Thien region. At the same time, they would collaborate with the Central Highlands battlefield, mobilize the whole force for a general offensive attack to win big victory when the time comes. This is a sound combat plan, ensuring that the campaign be able to engage the enemy in all three strategic areas, meeting the requirements and targets of the “basic plan” and “chance plan” in accordance with the direction of the Politburo and the Central Military Commission.

To implement the plan, we made some adjustments on force deployment and formed up 5 areas, namely: Quang Tri, Northern Thua Thien; Hue; Southern Hue and an area for attacking on communication lines. Each area consists of regular force, local force and militia and guerilla. Steering boards were also established in each area for direct command of force deployment and combat collaboration when the opportunity arises. Distinctively, the main direction for offensive which had been set up in the west of Hue was shifted to the southwest of Hue. This is because southwestern region of Hue is a dangerous and vital direction to the enemy. Moreover, from this point, we could easily cut through road number 1 (from Hue to Da Nang route) and block up the enemy. The campaign, in reality, has taken place according to our plan, contributing to destroying a strong defensive area of the enemy and liberating completely three provinces of Quang Tri, Thua Thien and Hue in a short time.

2. Seizing the opportunity, transforming the posture flexibly creating synergy to liberate completely the province of Quang Tri.

Our resounding victories in Tay Nguyen and the enemy’s wrongful deployment of forces made them chaotic and extremely panicked in the region of Tri – Thien. With fast changes of the situation, the Tri - Thien military zone and the No2 Corps showed their determination to seize the opportunity, mobilize all forces to liberate the provinces of Quang Tri, Thua Thien and Hue city by a general and comprehensive offensive, annihilating the majority of the enemy and preventing them from “strategically re-grouping” in Da Nang; meanwhile involving local forces in engaging the enemy, assisting and encouraging the mass to capture and hold the ground, facilitating the campaign to the complete victory.

3. Furthering the opportunity, proactively creating chances to annihilate the enemy part by part, liberate Thua Thien – Hue and prevent the enemy from regrouping in Da Nang.

Given the fact that Quang Tri was lost, Thua Thien – Hue was in severe danger, No 1 Road was cut off, on the spot force was heavily damaged, reinforcements came with difficulties, the enemy was unable to hold a counterattack and recapture the lost ground but to retreat and regroup in Da Nang. Anticipating the enemy’s intention, the High Command of the campaign ordered the Division 325 to hold the captured ground on the No1 Road, break down the enemy’s counterattack, advance towards both Mui Ne and Huong Dien directions, take control of part of the No1 road with a length of about 10km preventing the enemy from recovering their critical Hue – Danang communication line. In addition, the High Command also ordered Division 324 to abandon Bong and Nghe mounts, advance to the plain, cut off the enemy’s retreat to Tu Hien and Thuan An estuaries; the 164 artillery brigade to move to 75 and 76 hills to give suppressive fire to our units and block up the two estuaries. The enemy was extremely chaotic because their retreat had been blocked up and their rear was under our attack. Thousands of vehicles and the remaining enemy troops concentrating on No1 road and at the Tu Hien and Thuan An estuaries were quickly destroyed. In particular, on 24 March 1975 when the high command of the No1 Corps of the South Vietnam decided to abandon Hue city, its No1 Devision and the whole enemy troops in Tri – Thien – Hue were almost under our control. This is one of the important factors contributing to the victory of the Tri – Thien campaign. Reviewing the campaign, researchers hold that our cutting off No1 road and blocking the enemy’s retreat in Tu Hien and Thuan An estuaries have created the most favourable conditions for annihilating the enemy completely.

The art of furthering the opportunity in the campaign is also manifested in the way that when the chance arose, all the forces involved in the campaign speeded up and launched continuous attacks making the enemy unable to recover. Notably, the fight to capture Phu Gia and Lang Co passes took place so recklessly and quickly that though the enemy had laid hundreds of kilograms of explosive charge on the Lang Co bridge they had not enough time to detonate to stop our advance. Moreover, the campaign not only liberated Tri – Thien – Hue completely but also went on capturing Hai Van pass creating posture and favourable conditions for our troops to launch attack into Da Nang.

Nguyen Huy Thuc