The attacks on Da Nang (29 January – 11 February 1968), were a series of attacks in the Tet Offensive launched by the North Vietnamese People’s Army of Vietnam (PAVN) and the Viet Cong (VC) during the Vietnam War. The attacks were repulsed by combined United States Marine Corps (USMC), United States Army, Army of the Republic of Vietnam (ARVN) and Republic of Korea Marine Corps (ROKMC) forces with the PAVN/VC suffering heavy losses.
Background Da Nang was a major base area for United States and South Vietnamese military forces supporting operations throughout I Corps. Da Nang Air Base was one of the major air bases used for offensive air operations within South Vietnam and for the support of USMC and ARVN forces. Naval Support Activity Danang operated extensive logistics facilities on the Tiensha (Tiên Sa) peninsula east of the city. Marble Mountain Air Facility supported USMC helicopter operations throughout southern I Corps. III Marine Amphibious Force (III MAF) had its headquarters at Hill 327 west of the Air Base, while ARVN I Corps had its headquarters north of the Air Base.
With the departure of the 5th Marine Regiment to support operations further north in I Corps, there was only one Marine infantry regimental headquarters in the extensive Da Nang Tactical area of responsibility (TAOR). Colonel Ross R. Miner's 7th Marine Regiment with all three of its battalions had the responsibility for the northern, western and southwestern sectors. 2nd Battalion, 7th Marines was in the north, 1st Battalion, 7th Marines was in the center and 3rd Battalion, 7th Marines was in the south. With the departure of the 2nd Battalion, 5th Marines in mid-January for Phu Bai Combat Base, the 3/7 Marines extended its area of operations to include An Hoa Combat Base to the south. Miner attached two additional companies to the 3/7 Marines, Company L, 3rd Battalion, 5th Marines and Company H, 2/7 Marines to cover its extended area.
A conglomeration of Marine support units, ARVN, ROKMC and two Marine infantry battalions attempted to secure the remaining area. In the Da Nang Vital Area, the artillery regiment, the 11th Marine Regiment, continued to oversee the Northern Sector Defense Command and the 1st Tank Battalion, the Southern Sector Defense Command. In both these sectors support troops doubled as infantry, manning fixed defensive positions and conducting patrols. Major General Donn J. Robertson, the 1st Marine Division commanding general, kept under his direct control the 3/5 Marines and the 2nd Battalion, 3rd Marines. Located between the Cầu Đỏ and Thanh Quýt Rivers and on either side of Highway 1, the two battalions provided the last line of defense before the so-called "Vital Area." The most eastern of the battalions, the 2nd, shared its area with the 3rd Amphibian Tractor Battalion, which was responsible for the coastal sand flats south of Marble Mountain. Below the Marine battalions, the ROKMC 2nd Marine Brigade secured the Hội An sector and the southeastern approaches above the Ky Lam River to Da Nang Air Base. Behind the Marine and Korean lines, the ARVN 51st Regiment deployed in support of the South Vietnamese Revolutionary Development program. With both fixed-wing and helicopter gunships and more than 120 artillery pieces ranging from 4.2-inch mortars to 175 mm guns, Robertson was confident that he could counter any threat that the enemy posed to Da Nang despite the thinness of his manned defenses.
In the Da Nang sector, the tempo of operations had picked up during the last weeks of January. The ROKMC, while not finding any sizeable forces, continued to encounter small enemy units and boobytraps which took their toll. In the 7th Marines sector, the Marines described the same type of activity as well as increased enemy infiltration. The 3/5 Marines reported "a definite increase of enemy harassment" and the movement of sizeable enemy units into the Go Noi Island area (). Lieutenant Colonel William K. Rockey, the 3/5 Marines commander, commented on the "increasing frequency and ferocity" of enemy contacts. He remembered that because of the number of casualties his battalion sustained, "it was necessary to employ administrative personnel on patrols" with "clerks, cooks, and drivers" on line. In one operation near Dien Ban, the ARVN 51st Regiment sustained losses of 40 men killed, six missing, and 140 wounded while accounting for about 80 enemy dead and 13 prisoners.
While activity in the Army's 23rd Infantry (Americal) Division’s areas of operations in Quảng Ngãi and Quảng Tín Provinces was somewhat diminished, there was enough enemy in northern and central I Corps to cause concern for both the American and South Vietnamese commands. On 27 January, COMUSMACV General William Westmoreland announced a ceasefire to be observed by Allied forces for 36 hours beginning at 18:00 on 29 January in honor of the Tết holidays. Although authorizing the ceasefire, he warned all American commanders to be unusually alert because of "enemy increased capabilities ." At 17:00 on 29 January, Westmoreland cancelled the truce in the entire I Corps sector. Robertson remembered that "the ceasefire was to be in effect… and the regimental commanders reported intense fire from the enemy and requested authority to continue artillery fire, if necessary…" Robertson granted the request and then "about 18:40 we got the word from III MAF that the ceasefire had been called off.”
For some time, the American forces had been aware that the PAVN/VC was about to launch some type of major offensive. Westmoreland was convinced that this big push would come either just before or right after Tết, but not during the holidays and probably at Khe Sanh and in the Vietnamese Demilitarized Zone sector. At Da Nang, III MAF knew that the PAVN/VC were on the move. Marine and Army reconnaissance flights using infrared technology and XM-3 "People Sniffer" airborne personnel detectors (APD) mounted on UH-1 helicopters indicated strong enemy concentrations in the hills near Hiếu Đức west of the 7th Marines. Lieutenant Colonel William J. Davis, the commanding officer of the 1/7 Marines, recalled that his unit began to take fewer casualties from surprise firing devices or boobytraps and began to suspect that enemy troops unfamiliar with the terrain might be attempting to move into his sector. Davis notified the division headquarters of his findings. According to Davis, a few hours later, Robertson called a division briefing for all battalion commanders. At the briefing, the division G-2 or intelligence officer, told the assembled officers that "they are finally going to come out and fight. We don't know why, but we know they are!" He later confided to Davis, "Bill, your phone call was right on the money! I called all the regiments and battalions and the same was happening to them."
On the evening of 28 January, just west of Hiếu Đức, a Marine squad from Company C, 1/7 Marines ambushed a three-man VC reconnaissance patrol. The Marines killed two and wounded the third. The Marines evacuated the survivor to the Naval Support Activity hospital where he died of his wounds. Before his death, however, the Vietnamese identified himself as Major Nguyen Van Lam, the commanding officer of the R-20th Độc Lập Battalion. From the recovery of Lam's notebook and a detailed sketch map of Hill 10, the location of the 1/7 Marines' command post, the R-20 commander was obviously on an exploration mission to discover any vulnerability in the Marine battalion's defences.
From other sources, the Marine command learned of other ominous measures taken by the PAVN/VC forces in the Da Nang sector. According to intelligence reports, on 15 January, Group 44, the forward headquarters of the PAVN/VC Military Region 5, moved from the hills in western Quảng Nam Province, to an advance position on Gò Nổi Island. On 29 January, Marine intelligence officers received a reliable report that the PAVN 2nd Division also had established its command post in western Gò Nổi. From the details of the other recovered documents, the VC obviously were making an extensive reconnaissance of the Da Nang area giving descriptions of military structures, distances, weapons and other information that would be of value to an attacking force. Additional intelligence tended to confirm the enemy was about to initiate something big. The ARVN 51st Regiment operating in the southern sector of the Da Nang area of operations came across evidence including documents pointing to a buildup of PAVN/VC strength together with probes of Allied defenses. On 29 January, a local village chief told the security officer of the Naval Support Activity at Camp Tiensha that about 300 VC would attack the Marble Mountain transmitter that night. That same day, the 1st Marine Division notified III MAF that "usually reliable sources" told of staging areas south of Da Nang for an impending attack. Finally, according to Marine intelligence officers, another "very reliable source" flatly stated "that the time of attack throughout MR (Military Region) 5 would be" at 01:30 and no later than 02:00 on 30 January.
PAVN/VC forces throughout South Vietnam were about to strike. In I Corps, the Allies learned from a defector that the enemy planned an attack against Quảng Ngãi City. According to this former member of the VC 401st Regimental Security Guard, local VC cadre stated that "the war had lasted too long and the Front had to seek a good opportunity to stage a great offensive that would bring the war to an early end." Further, the National Police reported that VC local leaders from Quảng Tín, Quảng Nam and Quảng Ngãi Provinces met in a base area in the hills of northern Quảng Ngãi to plan attacks on Chu Lai and on Quảng Ngãi City.
While the PAVN/VC concentrated their forces for the large offensive, many of these units suffered from too many rapid replacements and in some cases from poor morale. As the defector from the 401st later revealed, his unit lacked "weapons, experienced soldiers, and transportation manpower." He personally believed the plans were impractical and deserted at the first chance he had. Another PAVN soldier, who infiltrated from North Vietnam after receiving a year's training as a radioman in Hanoi, was thrust into one of the attacking battalions south of Da Nang so hastily that he never learned the name of his unit let alone those of his officers. Two members of a VC engineering company, also in the Da Nang area, later recounted that nearly 80 percent of their unit was from North Vietnam. The PAVN obviously were bringing the local VC main force units up to strength, even if to do so they had to bring in replacements from the north. For example, while the R-20th attempted to maintain a full complement of 400 men through the recruitment or impressment of local villagers and infiltration of North Vietnamese "volunteers," intelligence sources rated the unit only "marginally effective."