Editing Easter Offensive (section)

===I Corps – Quảng Trị===
{{Further|First Battle of Quang Tri}}
[[File:DRVA.jpg|300px|right|thumb|PAVN 122mm artillery battery goes into action on the Kon Tum front]]
The offensive began at noon on 30 March 1972, when an intense artillery barrage rained down on the northernmost ARVN outposts in Quảng Trị Province.

Two PAVN divisions (the [[304th Division (Vietnam)|304th]] and [[308th Division (Vietnam)|308th]] – approximately 30,000 troops) supported by more than 100 tanks (in 2 Regiments) then rolled over the Demilitarized Zone to attack I Corps, the five northernmost provinces of South Vietnam. The North Vietnamese 308th Division and two independent regiments assaulted the "ring of steel", the arc of ARVN firebases just south of the DMZ.

From the west, the [[312th Division (Vietnam)|312th]], including an armoured regiment, moved out of Laos along [[National Route 9 (Vietnam)|Route 9]], past [[Khe Sanh]], and into the Quảng Trị River Valley. Significantly, allied intelligence had failed to predict both the scale of the offensive and the method of attack, giving PAVN "the inestimable benefit of shock effect, a crucial psychological edge over defenders who had expected something quite different."{{sfn|Palmer|1978|p=317}}
[[File:EoF1.jpg|thumb|left|200px|PAVN offensive in I Corps]]

On 1 April, South Vietnamese General Giai, ordered a withdrawal of the 3rd Division south of the Cửa Việt/[[Thach Han River]] in order for his troops to reorganize. The following morning, ARVN armoured elements held off a PAVN offensive briefly when the crucial Highway QL-1 bridge over the Cửa Việt River at [[Đông Hà]] was blown up by Capt. [[John Ripley (USMC)|John Ripley]], adviser to the [[Republic of Vietnam Marine Corps|3rd Vietnamese Marine Battalion]].<ref name=Melson>{{cite book|last=Melson|first=Charles|title=U.S. Marines in Vietnam: The War That Would Not End, 1971–1973|publisher=History and Museums Division, Headquarters, U.S. Marine Corps|year=1991|url=https://archive.org/details/TheWarThatWouldNotEnd|isbn=978-1482384055}}{{PD-notice}}</ref>{{rp|56–60}} The initial PAVN units were then joined by the [[320th Division (Vietnam)|320B]] and [[325th Infantry Division (Vietnam)|325C]] Divisions.

Simultaneously, the [[324th Division (Vietnam)|324B]] Division moved out of the [[A Sầu Valley]] and advanced directly eastward toward Fire Bases [[Firebase Bastogne|Bastogne]] and [[Firebase Checkmate|Checkmate]], which protected the old imperial capital of Huế from the west.

The North Vietnamese advance had been timed to coincide with the seasonal [[monsoon]], whose {{convert|500|ft|m|0}} cloud ceilings negated many U.S. airstrikes.{{Refn|This situation was exacerbated by the attempt to [[Rescue of Bat 21 Bravo|rescue Air Force officer Lt Col Iceal Hambleton ("Bat-21")]], who had been shot down on 2 April by a surface-to-air missile behind PAVN lines. During the 12-day attempt to rescue him, a no-bombing/no-shelling zone was imposed south and west of the [[Cam Lo River]], a tragic decision for the 3rd Division.{{sfn|Andrade|1995|pp=94–95}}|group=Note}} PAVN advance elements were soon followed by anti-aircraft units armed with new [[ZSU-57-2]] tracked weapon platforms and man-portable, shoulder-fired [[Strela 2|Grail missiles]], which made low-level bombing attacks hazardous.

[[Camp Carroll]], an artillery firebase halfway between the Laotian border and the coast, was the linchpin of the South Vietnamese northern and western defense line and was the strongest obstacle to the North Vietnamese before Quảng Trị City. The camp was cut off and surrounded. On 2 April, Colonel [[Pham Van Dinh]], commander of the 56th ARVN Regiment, surrendered the camp and his 1,500 troops.{{sfn|Trưởng|1980|p=30}} Later in the day, ARVN troops abandoned [[Mai Loc Camp|Mai Loc]], the last western base. This allowed North Vietnamese forces to cross the [[Cam Lộ]] bridge, 11 kilometers to the west of Đông Hà. PAVN then had almost unrestricted access to western Quảng Trị Province north of the [[Thạch Hãn River]].
[[File:ARVN M-48 tanks are positioned near the Dong Ha River overlooking QL-9, April 1972.jpg|thumb|right|ARVN M-48 tanks are positioned near the Dong Ha River overlooking QL-9 during the Easter Offensive, 10 April 1972]]

On 21 April, Abrams notified the U.S. [[United States Secretary of Defense|Secretary of Defense]] that

<blockquote>In summary...the pressure is mounting and the battle has become brutal...the senior military leadership has begun to bend and in some cases to break. In adversity, it is losing its will and cannot be depended upon to take the measures necessary to stand and fight.{{sfn|Sorley|1999|p=330}}</blockquote>

The PAVN advance was slowed by delaying actions for three weeks, and the South Vietnamese launched several counterattacks, but on the morning of 27 April, the North Vietnamese came on again, launching multi-pronged attacks against Đông Hà (which fell on the following day) and advancing to within 1.5 kilometers of Quảng Trị City. General Giai had planned a staged withdrawal from the city to consolidate south of the Thạch Hãn, but bewildered by conflicting orders from Lãm and Giai, most ARVN formations splintered and then collapsed, conceding most of the province north of the city.<ref>Trưởng, p. 38. See also Fulghum and Maitland, pp. 145–147. For those units that did not fall apart, see ibid., p. 147. For Lãm's culpability, see Andrade, p. 150.</ref>

On 29 April, Giai ordered a general retreat to the [[Mỹ Chánh River]], thirteen kilometers to the south. U.S. military advisors in Quảng Trị called for emergency helicopter extraction and, on 1 May 132 survivors were evacuated from Quảng Trị, including 80 U.S. soldiers.

The exodus of ARVN forces was joined by tens of thousands of South Vietnamese civilians fleeing from the fighting. As the mass of humanity jostled and shoved its way south on Highway 1, it presented an inviting target for North Vietnamese artillerists.{{sfn|Trưởng|1980|pp=45–46}} They were soon joined by PAVN infantry, who moved by the flank to attack the column. ARVN units, with no leadership and all unit cohesion gone, could muster no defense. Meanwhile, to the west, Fire Support Bases Bastogne and Checkmate had fallen after staunch ARVN defense and massive [[Boeing B-52 Stratofortress|B-52 bomber]] strikes, which inflicted heavy casualties.{{sfn|Sorley|1999|p=329}}

Giai evacuated the last of his forces from Quảng Trị City, which fell to PAVN forces on 2 May. That same day General Lam was summoned to Saigon for a meeting with President [[Nguyễn Văn Thiệu]]. He was relieved of command of I Corps and replaced by Lieutenant General [[Ngô Quang Trưởng]], commander of IV Corps.{{Refn|Instead of sacking Lam for poor leadership, Thieu promoted the politically connected general to the Ministry of Defense.{{sfn|Andrade|1995|p=171}}|group=Note}} Trưởng's mission was to defend Huế, minimize further losses, and retake captured territory. Although saddled with raw troops and constantly countermanded by his superiors, General Giai had conducted a reasonably good defense. Even Trưởng pleaded his case with Thiệu, wanting to keep Giai in command of the 3rd Division.{{sfn|Trưởng|1980|pp=62, 166}} It was in vain. Giai, who was to be made the scapegoat for the collapse, was tried for "desertion in the face of the enemy", and sentenced to five years in prison.{{sfn|Fulghum|Maitland|1984|p=150}}