Commanders Diary

The 4th 23rd Tomahawks Commander's Page

Daily Diary Transcript
Lieutenant Colonel Clifford C. Neilson (Col. Ret.)
Commanding Officer
4th Battalion (Mechanized), 23rd Infantry Regiment, 25th Infantry Division
12 May -13 November 1968
Tay Ninh Province, Republic of Vietnam
CTZ (Combat Tactical Zone) III


The  diary entries were made nightly over a 6-month period in 1968 and were  transcribe in 2003-4. Although the entries are legible, the meaning of  the many abbreviations, acronyms, and short hand notations within the  daily entries is likely to be puzzling to a reader many years later.  Some were to me and I was the writer! This transcript faithfully reproduces the entries as written in bold 14-point font. Explanatory notes for abbreviations, acronyms, and short hand notations are shown inside 14-point font brackets [...] the first time used. Historical and non-diary entry specific  explanatory material providing context and technical details appear  after entries in 12-point font italic.   

The  diary is divided into, this Preface and 7 chapters, one for each of the  months May thru November 1968 in which I commanded the Battalion and a  glossary. (For Internet posting, chapters will be divided into 7-day  weeks.)   

 Background of the Time and Geography Included in the Diary Entries:   

During this period, the land mass called, Vietnam, was divided into two parts. The communist-style Democratic Republic of Vietnam (DRV) (or more familiarly North Vietnam) controlled the northern part; Ho Chi  Minh led the government. Its military forces were usually referred to  by the US military structure as the North Vietnamese Army (NVA). The USSR and China supported the DRV both, with supplies and diplomatically.   

The ostensibly, democratic, Republic of Vietnam (RVN) (or  more familiarly South Vietnam) controlled the southern part. The US  military structure usually referred to RVN military land forces as the Army of the Republic of Viet Nam (ARVN) and ARVN Marines. In addition to the United States, the governments of, Australia, New Zealand, South Korea, Philippines, and Thailand supported the RVN with troops. 

Within  the RVN population was a large opposition guerrilla force, the Viet  Cong (VC). The VC were RVN citizens, armed, organized, and supported by  the DRV who fought as guerrillas against the US and RVN regular forces. The RVN was divided into civil government entities called provinces; each province was divided further into districts. All US Military operations within RVN were under the command of the Military Assistance Command Vietnam (MACV) with headquarters in Saigon. Allied forces were under the Operational Control (OPCON) of MACV. During the period of this diary, General William Westmoreland commanded MACV.   

MACV superimposed on the RVN civil provincial structure four Roman-numeral military corps-like organizations called Field Force Vietnam (FFV). MACV assigned US and allied combat and support units to the FFV as they  arrived in country and occasionally shifted these units between FFV to  meet changing circumstances. Additionally, MACV assigned US military personnel as advisors to ARVN  units down to company-sized units.   

All  US forces within the FFV geographic area of operations, combat and  advisor, were under the FFV commander. Within a FFV area, US combat  units were assigned a Tactical Area of Operational Responsibility (TAOR) (frequently shortened to Area of Operations (AO).    

In  1968, III US FFV was responsible for the Provinces in which the 25th  Infantry’s TAOR was located.  Major US Army units, operating in III FFV,  May thru November 1968, in addition to the 25th Division, included the  1st Infantry Division, 11th Armored Cavalry Regiment, and the 199th  Infantry Brigade (Bde) 

25th Infantry Division Organization and Tactical Area of Operations   

This  diary covers a period when the 25th Infantry Division TAOR, encompassed  the Provinces from the north edge of the Saigon, Capital Military  District, along major highways northwest of the city of Cu Chi, to the  Cambodian border. The Division combat forces consisted of: 3 Bde  Headquarters, 6 Infantry and 3 Mechanized Infantry Battalions, an Armored Cavalry Squadron, and 4 Artillery Battalions. It  also had the normal complement of, organic combat support and service  units, as well as, non- Division attached and supporting units. The  combat forces were under the operational control (OPCON) of one of the  three Brigades. Division and 3rd Bde headquarters were at Cu Chi, 1st Bde at Tay Ninh, and 2d Bde at Dau Tieng. During May thru November 1968, the 4th Battalion (Mechanized), 23rd Infantry Regiment (4th/23rd) was OPCON to each of the Brigades, but primarily to the 1st Bde.   

The following adapted from a “Tropic Lightning” News article:     

"  In addition to screening secondary roads, the division maintained  round-the-clock security operations on the extensive main routes of  supply in the TAOR. These Main Supply Routes (MSR) were, Route 1, from Saigon to Cu Chi to Go Dau Hau; Route 22, from Go Dau Hau to Tay Ninh City; Route 4, from Tay Ninh City to Rau Co; Routes 13, 26 and 239 from Tay Ninh City to Dau Tieng; and Route 8A from  Cu Chi to Phu Cong. The only portion of the TAOR that the Division did  not enter in force during May-November 1968, was the sparsely populated War Zone “C” jungle area north of the Tay Ninh, Bau Co, Dau Tieng axis. This area  was subjected, however, to extensive active surveillance, by both aerial and long-range ground reconnaissance, conducted by squad and  platoon size units. Extensive, Air Force, B-52 bombing missions  (nicknamed ARC LIGHT) and tactical fighter strikes were made throughout  War Zone C, upon enemy base camps, supply concentrations and other  targets of opportunity."   

During this 6 months of diary entries, the Tay Ninh Base Camp (TNBC) was the 4th Battalion's "Home". TNBC, located about 6 miles northwest of Tay Ninh  City, was a large circular shaped, military/“city-like”, semi-permanent,  garrison. It was surrounded by 3 Concertina wire (coiled, razor barbed,  wire) fences interspersed with watch-towers and fighting bunkers. It was the  “permanent” home for probably at least a thousand US Army and Air Force  supply, maintenance, and support troops and the site of their living  quarters and working facilities in RVN. In addition to US military  personnel, there was a sizable contingency of non-native civilian  contractors including Pacific Architect & Engineer (PAE), which provided specialized support. At the start of each day,  local Vietnamese day laborers would enter the base to perform  additional support tasks. And last but not least, it was the base for  the Philippine Civil Assistance Group (PHILCAG).   

Located  within TNBC's perimeter was a large, hard surfaced airstrip capable of  landing C-130 USAF aircraft; a mobile army surgical hospital (MASH); a  large ammunition bunker; a Petroleum, Oil, and Lubricant (POL) "farm";  an outdoor movie theater, swimming pool, Post Exchange complex; and  separate clubs for officers, non-commissioned officers, and enlisted men.    

TNBC and the personnel assigned to it, provided logistics support to the 1st Bde, 25th Infantry Division; 3 to 5 combat battalions (i.e. 4th /23rd) OPCON’ed to the 1st Bde, which operated generally in the Tay Ninh area; Special Forces camps along the Cambodian border; and occasionally to ARVN units.   

For  each combat battalion, there were barracks, mess halls, and offices.  Non direct-combat battalion personnel, performing duties such as  personnel and supply clerks, cooks, medics, mechanics; walking wounded;  personnel going on or returning from Rest and Relaxation (R&R)  furlough; and soldiers either arriving or departing RVN occupied these facilities under the “watchful eye” of the Battalion  Executive Officer (XO) and each Company's XO. Also, during the infrequent times when the battalion was withdrawn from combat status to rest and  refit (“stood down”), these combat elements returned to TNBC to use  these base camp facilities.    

Permanently  assigned base camp support and combat unit personnel, when at TNBC,  were responsible for its defense and took turns, manning the perimeter  nightly, after their regularly daytime duties were completed. When a  battalion "stood down" it provided a contingency to defend the base camp  mission.   

Each  day, a large re-supply convoy would leave Saigon, bound for Cu Chi,  TNBC, and Dau Tieng. Convoy escort responsibility was shared by the 3rd Squadron, 4th Cavalry Regiment (nicknamed: The Three-quarter CAV); The 4th /23rd and the 1st Battalion (Mechanized)/5thInfantry (nicknamed: The First of the Fifth Mech, Bobcats). These escort duties, resulted in many combat actions during May- November 1968.   

Tay Ninh City, capital of Tay Ninh Province, was a bustling metropolis. Its primary claim to fame was being the site of the Cao Dai Temple Complex.  The Cao Dai were an offshoot of the Catholic-Buddhist religion and  vehemently, anti-NVA. This high-walled, temple complex could be likened  to their own “Vatican City” and they fought bravely on numerous occasions to prevent the NVA from  seizing it.   

The most prominent geographic landmark, in the province, was Nui Ba Den Mountain (allegedly “Black Virgin” or “Dark Lady” Mountain” in Vietnamese.) It’s  western base sat about 6 miles east of TNBC. At an altitude of six  thousand feet, it appeared to “thrust” out of the surrounding plain and  its summit provided unparalleled observation in all directions. On the mountain’s  top, was a US Army communication station, defended by a detachment of 25th Infantry Division soldiers. Around the base of the mountain, was a  network of unimproved trails and rutted roads. On the lowest slopes,  were banana plantations and a US Army-operated and defended, “Rock  Quarry”. Everything else, between the top and bottom, was controlled by the NVA. Throughout May-November 1968,  ownership of this middle layer was contested bitterly by elements of the  25th ID, including the 4th /23rd.   

North of TNBC and close to the Cambodian border, were the remains of a Colonial French Fort (FF).  It was rebuilt and occupied by US forces. Stationed at the FF were US  Special Forces units and a Battery 175mm cannon, capable of firing up to  25 miles.  Escorting re-supply convoys to FF was a frequent task of the  4th/23rd.   

About 30 miles northeast of TNBC was the village of Dau Tieng (DT). It housed the Michelin rubber plantation headquarters and processing  facilities. The rubber tree plantations were vast and seemed to stretch  in every direction for miles. Throughout the plantation area were small  hamlets for the workers and used frequently as sanctuary by the NVA. DT usually housed the headquarters of the 2d  Bde, 25th Division. Virtually every day, elements of the 4th /23rd, escorted the re-supply convoy from TNBC to a check-point where escort responsibility reverted to the 1st /5th Mech. After the trucks were unloaded in DT, the convoy returned to TNBC under the protection or the 1st /5thand 4th /23rd. 

The Organization, Equipment, and Mission
The 4th Battalion (Mechanized), 23rd Infantry Regiment.

The 4th Battalion was organized under the MTOE 7-46, 7, 8G series with: 

Headquarters & Headquarters Company (HHC). HHC had assigned the battalion staff, Reconnaissance Platoon, Heavy  (4.2") Mortar Platoon, and Flame Thrower Platoon. Habitually attached:  Artillery Liaison Officer and Engineer Platoon Leader.
 • Three line companies (Alpha, Bravo, Charlie).Each company had three rifle platoons and a mortar platoon. Habitually  attached: artillery forward observer (FO) with the company command group  and a medical person (medic) with each platoon.
 • Service & Supply Company (Delta). Delta Co had medical and supply personnel, mechanics, and cooks, some of whom were attached to the combat elements.
The battalion normally conducted daily operations from two locations:
 • The combat elements - A, B, C Companies, and the reconnaissance, mortar, and flame thrower platoons - commanded by their company and platoon leaders defended the night defensive positions (NDP),  departing each morning to conduct combat operations. When an artillery  unit was located at the NDP, which was the usual practice, the location  was designated a fire support base (FSB). When artillery units were  present, they played a vital defensive role. But, in several instances,  operations were conducted from the base camp and on some occasions there  were no artillery units in the NDP.
The Battalion CO, the  Intelligence Officer (S2), Operations Officer (S3) and his assistant,  and the Command Sergeant Major (CSM) operated from the NDP with combat elements. Usually supporting at the NDP were detachments from:  the Medical Platoon with the Surgeon manning the aid station; the Mess  Platoon operating a mess hall; the Maintenance Platoon, repairing  equipment; and the Supply Platoon, re-supplying food, water, ammunition,  vehicles and weapons.
 • The Supply and Service Elements of  each organization normally operated from the TNBC. The Battalion XO commanded Battalion personnel in the camp. Assisting  him, were the Delta Co. Commander, Adjutant (S1), Logistic Officer (S4),  Civil Affairs Officer (S5), Communications Officer, Motor Officer,  Chaplain and the Company XOs and First Sergeants.
Sometime after November 1968, changes were made to the MTOE. Among the changes, was the addition of a Combined Reconnaissance & Intelligence Platoon (CRIP)   

The 4th Battalion, executed five distinct missions:

  1. Convoy escort & protection    
  2. Reconnaissance in Force (RIF) (mounted and dismounted)    
  3. Defense of base camps and fire support bases    
  4. Airmobile assault.   
  5. ARC LIGHT sweeps