The Best Damn Regiment That You Will Ever See

Many units of all types – large, small, and everywhere in between – deployed to Vietnam during the war that raged there from 1965, when US ground combat units began deploying, into the early 70s. However, only a single armored cavalry regiment served in-country. That was the 11th ACR, the famed Blackhorse that deployed there from September 1966 to March 1972.

27 armored cavalry platoons formed the regiment’s beating heart. Each platoon was the smallest combined arms force in the Army. Under the platoon leader were three scout sections of two tracks each, a rifle squad, and a mortar squad. Before deploying, tanks served in the platoon, but I’m getting ahead of myself.

To go back a bit, 1965 saw the beginning of the Army’s major troop commitment to Vietnam. In that year, General Westmoreland requested the a mechanized infantry brigade be deployed to Vietnam. He foresaw a role for this unit in missions like route security, convoy escort, etc. He wanted infantry, not tanks. His was an infantry-centric view, understandable, yet also limiting in terms of force options.

Based on the French and ARVN experience with armor supplied by the US, Military Assistance Command Vietnam had determined that large areas of South Vietnam were inaccessible to tanks. ₂ Westmoreland and his staff also believed that heavy armored forces had little or no role to play in counterinsurgency.

Armor branch worked overtime in 1965 to get the regiment into combat. One of the key project officers was a very determined lieutenant colonel named George S. Patton. The Army Chief of Staff finally agreed to the proposal, and Westmoreland relented on the condition that the line troops get rid of their medium tanks.

So when the Blackhorse deployed to Vietnam in 1966, the regiment’s nine cavalry troops left their M48s at home, swapping them for M113 APCs. This left the regiment with its three organic tank companies, each of which contained 17 tanks.

The MACV commander also told the regiment to leave behind its M114 armored reconnaissance vehicles. In hindsight, this was a smart decision since the 114 was a sad little track that had performed poorly in tests by ARVN cavalry units. It was under-powered, under-armored, and tended to get stuck in even the smallest ditches. The regiment replaced its 114s with M113 APCs. When it went downrange to Vietnam, the Blackhorse deployed with near 300 PCs.

A lot of finagling, wrangling, and debate went on at the Pentagon as Army leaders tried to turn Westmoreland’s request into an actual unit in-country. Armor branch felt convinced that an ACR with its firepower, flexibility, and mobility presented a perfect solution. Infantry branch, on the other hand… not so much. But the Blackhorse had one indisputable thing going for it. No other equal-sized ground unit possessed the organic ability to shoot, move, and communicate so effectively.

With ingenuity common to the cavalry, Blackhorse troopers modified their PCs by adding extra machine guns and armored shields. They gave their new tracks a name that matched the regimental ethos: Armored Cavalry Assault Vehicle. The design proved so successful, that it was adopted by armor and mechanized units throughout the Army in Vietnam. To this day, ACAV kits built in the 1960s can still sometimes be spotted on M113s in active service.

As I mentioned earlier, MACV (in the form of General Westmoreland) originally did not believe that a role existed for tanks in-country. So naturally, the Blackhorse immediately began proving him wrong. At the same time, other deploying units essentially snuck their tanks into Vietnam under Westmoreland’s nose. He finally relented, agreeing that units could bring their organic tanks along when they came in-country.

To put it simply, the Blackhorse excelled at the “holy trinity” of cavalry missions: reconnaissance, security, and economy of force. The regiment added another tactic which it perfected in Vietnam: Find the bastards, then pile on. This was an adaptation of the classic movement to contact in which the smallest possible unit (the tip of the spear) located the enemy. Tanks, ACAVs, artillery, helicopters, and tactical airpower then maneuvered rapidly to achieve overwhelming force. A 1967 armor study by Military Assistance Command Vietnam put it succinctly:

The armored cavalry squadrons have proven to be responsive to [the] concept of aggressive offensive action in [Vietnam] because of their balanced combined arms structure and inherent capability for quick response and extended independent action. The extensive firepower and combat strength of the armored cavalry squadron have dictated its more effective use in the role of a well balanced maneuver battalion rather than in its traditional roles. ₃

In his senior officer debriefing from 1970, Col Donn Starry, 41st Colonel of the Regiment, provided a detailed summation of pile-on tactics.

The “pile-on” concept used against local VC forces consisted of widespread reconnaissance by minimum forces – squads of the aero-rifle platoon, sections of ACAV’s or tanks. On contact the force built up by rapid deployment of as many other small units as could reach the fight.

When fighting against regular NVA forces, reconnaissance had to be conducted by at least platoon size elements, and in most cases by troop or company. The NVA fought as units, ambush was their preferred tactic.

The danger of losing a minimum size force to a well organized ambush was such that “pile-on” techniques used when fighting VC locals, while still appropriate in principle, had to accommodate to the enemy. However, force generation – the application of maximum force in minimum time was still the key to success. ₄

In regard to cross-country movement, the 1967 MACV armor study determined that that over 46% of the terrain in Vietnam was accessible to armor year-round. To a great extent, this assessment was based on work the Blackhorse did. The regiment took its vehicles into places no one could have foreseen previously, such as trackless jungles and lowland rice paddies.

Using a techniques called “jungle-busting,” cavalry troops moved straight into the densest wooded areas. They often operated in the jungle box, a formation that put two platoons in parallel columns with tanks leading. The troop’s third platoon moved behind them formed into a skirmish line. Describing how the regiment did this in 1967, Blackhorse veteran Don Snedeker wrote:

Noteworthy … is that all of these operations were off the roads, moving cross-country through the jungle, rubber plantations, and savannah grass–something that had been considered “impossible” just six months earlier. The mounted troopers provided the jungle-busting, mobile firepower needed to root out the VC, demonstrating to leaders up and down the chain of command that armored units could operate pretty much everywhere.  ₅

During the years that the Blackhorse served in Southeast Asia, the regiment’s troopers fought in many battles large and small. To cite one example, the Tet offensive of January-February 1968 shook the U.S. and South Vietnamese governments. The enemy launched ferocious attacks across South Vietnam.

At the time, the 11th ACR was engaged in tough combat in the northern sectors of the III Corps tactical zone. But regimental commander Col. Jack McFarlane had initiated contingency planning with his staffs. When the order to move came in the desperate hours of 31 January 1968, the Blackhorse disengaged, turned 180 degrees, and marched the reinforce embattled allied forces in the Saigon area.

3rd Squadron was furthest from the objective area, and pushed 100 kilometers. The other line squadrons had a shorter distance of 60 to 65 kilometers to cover. Moving in long columns, the regiment blew through the enemy road blocks, and moved to the sound of the guns. For this epic feat of gallantry in action, the Blackhorse received the prestigious Valorous Unit Citation.

The communists adhered to Mao Tse-tung’s combat philosophy: When the enemy advances, withdraw: when he defends, harass; when he is tired, attack; when he withdraws, pursue. ₆ When Mao wrote these words, he clearly had never heard of the 11th ACR. The Viet Cong and North Vietnamese Army never completely adapted to the aggressive tactics used by the Blackhorse, and as the years in Vietnam wore on, the regiment pushed deeper and deeper into the enemy’s sanctuaries.

Beginning in January 1969, the Blackhorse fielded the M551 Sheridan. The new tracks went straight to the cavalry platoons, which each lost one of their three scout sections. In return, the platoons each received a tank section in the form of three Sheridans.

The new tracks proved a powerful addition to the regiment’s firepower. But they came with a price. The Sheridan was a thin-skinned vehicle extremely vulnerable to mines and antitank weapons. Once completed with fielding, each line troop possessed nine Sheridans, for a total of 27 in each line squadron.

In May 1970, the Blackhorse served as a spearhead for the push into Cambodia, codenamed Operation Rock Crusher. Advancing into the Fish Hook area, the regiment captured Snoul, a key enemy hub. After the initial push, the regiment switched to search and clearance operations, destroying or evacuating major quantities of enemy supplies, armaments, and equipment.

Extract from 11th ACR operational summary for Cambodia

I’ve written a lot today about how the Blackhorse fought and where it went in Vietnam and Cambodia. But the 11th ACR was much more than machines and weapon systems. At its strong core, the regiment found its strength and combat power not from its machines, but from the troopers who made them come alive.

In quantifying the regiment’s performance in Southeast Asia, one historian wrote:

The 11th Armored Cavalry Regiment … bec[a]me one of the Army’s finest units in Vietnam. It rapidly moved beyond conventional expectations regarding armor’s ability to cross difficult tropical terrain. Often parceled out in squadron increments to avail larger commands of its precious armored firepower, the regiment would see action in many areas, with many different units. A series of excellent commanders and aggressive flak-vested cavalrymen would ensure that the Blackhorse gained an enviable combat reputation far out of proportion to their actual numbers. ₇

Most Blackhorse veterans don’t boast or brag about what they did, what they accomplished in that far-off time and place. But each trooper who wore the rearing stallion of the 11th United States Cavalry in Southeast Asia can say with honor:

I served in a proud regiment. I rode with the Blackhorse.

Allons, Never forget,
Mark
E 2/11 ACR 1985-89

Notes

1. The title of this article is a line from the chorus of the regimental song: Allons, Allons, The Pride Of Cavalry, The Best Damn Regiment That You Will Ever See.
2. MACV report Mechanized and Armor Operations in Vietnam, page 70.
3. Op. cit., page 166.
4. The cited passage is found on pages 17-18 of “Senior Officer Debriefing Report: Col Donn A. Starry, CO, 11th Armored Cavalry Regiment …”
5. The Blackhorse in Vietnam, page 39, by Donald Snedeker, Casemate Publishers, 2020. This is an outstanding book which is essential to understanding the regiment’s operations and history.
6. Mao’s philosophy is described in Mounted Combat in Vietnam, page 14, by General Donn Starry, GPO, 1978.
7. The cited passage is from page 76 of The Rise and Fall of an American Army – U.S. Ground Forces in Vietnam, 1966-73 by Shelby Stanton, Presidio Press, 1985.