Also in early March 1965 Johnson sent U.S. Army Chief of Staff General Harold K. Johnson on a mission to Vietnam. Returning to Washington at midmonth, General Johnson submitted to the president a report containing 21 recommendations, including an intensified air war against North Vietnam and the deployment of many more ground forces to Vietnam. Most of these proposals were approved, and in mid-June Secretary of Defense Robert McNamara announced additional deployments to a level of 75,000 men. In closing his report, General Johnson had raised the question of how much more the United States would have to contribute. In the margin, Secretary of Defense Robert McNamara wrote a blank check: "Policy is: Anything that will strengthen the position of the GVN [government of Vietnam] will be sent."
Meanwhile, General Johnson set in motion within the Army staff a study of how the war was being conducted that would have an enormous, but much delayed, impact on American involvement.
Reports through the late spring of 1965 indicated that the Army of the Republic of Vietnam (ARVN) could not survive without extensive additional assistance. On July 28, 1965, President Johnson announced to Americans that he was sending 50,000 more troops and that draft calls would be increased. "Additional forces will be needed later," he added, "and they will be sent as requested." Significantly, the president did not approve calling up reserve forces. The U.S. command in Vietnam quickly submitted requests for even more forces, and the buildup of American troops moved into high gear.
Shortly after the series of retaliatory air strikes against targets in North Vietnam were conducted in early February 1965, President Johnson authorized a continuing air campaign against the North that became known as Operation ROLLING THUNDER. Commencing in early March 1965 this bombing continued unabated, except for certain suspensions and restrictions, until October 31, 1968. It was in the conduct of the air war, however, that the greatest controversy arose over the administration's "graduated response" approach. The Joint Chiefs of Staff, as well as the field command, sought to apply massive force in the shortest possible time. Instead, frustrating impediments to this strategy were imposed by the civilian hierarchy. Even though the scope and magnitude of the air war continued to increase, albeit punctuated by numerous pauses of varying duration, the incremental approach permitted the Communists to make adjustments at successive levels and to put in place a continuously improving air defense system. After leaving office, Johnson reportedly told President Richard M. Nixon that all the pauses had been useless and that he regretted having ordered them. That notwithstanding, in March 1968 Johnson scaled back the bombing of North Vietnam to below the 20th parallel only, and in November of that year terminated it altogether.
In June 1964, General William Westmoreland had taken command of Military Assistance Command, Vietnam (MACV). This was an ominous appointment, for it was he who devised the strategy of attrition and search-and-destroy tactics that characterized the ground war through the end of his tenure. The measure of merit under this approach became the body count; the defining objective and the so-called crossover point became the point at which enemy soldiers were being killed at a greater rate than they could be replaced by infiltration from North Vietnam or by in-country recruitment in South Vietnam. "Accompanying the strategy," stated the Pentagon Papers, "was a subtle change of emphasisóinstead of simply denying the enemy victory and convincing him that he could not win, the thrust became defeating the enemy in the South." But that was not all: "Written all over the search and destroy strategy was total loss of confidence in the RVNAF [Republic of Vietnam Armed Forces] and a concomitant willingness on the part of the U.S. to take over the war effort."
Seeking to achieve this elusive goal, General Westmoreland made repeated requests for additional troops. In February 1966, only months after the first major increases, he came in with requirements that would raise the troop ceiling to 429,000. In 1967 he was back with further requests for major troop augmentation, beyond the 470,000 that by that point had been authorized. This time he presented two alternatives, one described as a "minimum essential" add-on of 80,500 troops, the other an "optimum" of some 200,000 additional, which would have brought the total authorized to 670,000. Washington approved neither of these packages; only a scaled down addition to a new total of 525,000 was authorized. Tolerance for additional commitments was running out.
With these forces, Westmoreland mounted large multi-battalion operations aimed at bringing Communist main force units to battle. The first of these engagements took place in the la Drang Valley in November 1965, when elements of the newly-deployed 1st Cavalry Division (Airmobile) took on some 2,000 People's Army of Vietnam (PAVN) troops from three different regiments. When the offensive was over, the Americans had inflicted an estimated 3,561 deaths on the Communists, losing 305 of their own in the process.
The American military establishment in the Republic of Vietnam (RVN) grew larger and more pervasive with each passing year. An elaborate system of base camps was developed, ports and airfields built or improved, and massive logistical support provided. Naval and Air Force elements grew proportionately, with naval gunfire as well as air elements contributing to the massive firepower at MACV disposal.
Meanwhile, the essence of Communist control over the populace, the Viet Cong infrastructure in the hamlets and villages, continued essentially undisturbed as pacification in the countryside and improvement of South Vietnamese forces were largely ignored. One positive development was that in May 1967 American support for pacification was pulled together under MACV control.
During 1967 General Westmoreland made three trips to the United States. Addressing various audiences, including the National Press Club, he said, "we have reached an important point when the end begins to come into view. I have never been more encouraged," he said in November, only weeks before the Communist 1968 Tet Offensive changed everything.
After the Tet Offensive, General Earle G. Wheeler made a trip to Vietnam and brought back a request for the deployment of some 206,000 additional American troops. This was yet another bombshell. General Westmoreland had been describing the Tet Offensive as a battlefield victory for Allied forces, one that had cost the Communists severe losses. Now this request for hundreds of thousands more troops seemed to undermine the credibility of that claim, just as the fact of the Tet Offensive itself had undermined Westmoreland's optimistic forecasts of the preceding year.
The request precipitated a comprehensive review of American policy on Vietnam. The result was a series of dramatic changes. The troop request was denied, the high-water mark of American commitment to the war was reached and passed, and Westmoreland was replaced as U.S. commander in Vietnam.
Westmoreland was not happy with the outcome of his tenure in command. Recalling bitterly "the prideful creatures in the bureaucratic jungles of Washington and Saigon," in his memoirs he summed up the experience in these terms: "As American commander in Vietnam, I underwent many frustrations, endured much interference, lived with countless irritations, swallowed many disappointments, bore considerable criticism."
The Pentagon Papers, meanwhile, offered their own summation of the situation: "At this writing, the U.S. has reached the end of the time frame estimated by General Westmoreland in 1965 to be required to defeat the enemy. It has committed 107 battalions of its own forces and a grand total of 525,000 men. The strategy remains search and destroy, but victory is not yet in sight."
On July 3, 1968 General Creighton Abrams formally assumed command of MACV, replacing Westmoreland. Abrams had, however, been de facto commander since shortly after the Tet Offensive. The successive increments of troop increases requested by Westmoreland, even though many of them had been scaled back, had brought the troop ceiling to 549,500 by the time Abrams took command. Actual deployments never exceeded 543,400, however, and on Abrams's watch there were no requests for more troops. Abrams understood the war and the dominant influence of the domestic support base, and he understood the need to work within the limits of that fragile and waning support. For a number of years, public, congressional, and, to some extent, even media backing had been strong, but that had been squandered as year after year went by with no discernible progress in bringing the war to a successful conclusion.
After the 1968 Tet Offensive, the Johnson administration changed its policy for the war from seeking military victory brought about largely by American forces to capping U.S. involvement and shifting the main burden to larger and more capable South Vietnamese forces. In that context, Abrams changed the tactics from search and destroy to clear and hold, the measure of merit from body count to population security, and the philosophy to conducting "one war" in which pacification, improvement, and modernization of the RVN armed forces and the conduct of military operations were integrated and of equal importance.
"The tactics changed instantly when General Abrams took over," recalled General Donn Starry. "We need to be more flexible tactically inside South Vietnam," Abrams had told President Johnson earlier in the year, and during the remainder of 1968 he set about arranging just that. Two early priorities were closing down the static defense of Khe Sanh, getting those forces into a more mobile role, and doing something about protecting Saigon from the frequent rocket and mortar attacks that had plagued it for years.
Soon Abrams had a planning element working on the combined campaign plan for the coming year, one that incorporated the essentials of the study that General Harold K. Johnson had commissioned in the spring of 1965. Known as Program for the Pacification and Long-Term Development of South Vietnam (PROVN), the study maintained that the way the war was being prosecuted under Westmoreland was not working, indeed could not work, and that a radical redirection of effort was required to achieve success. When the study was first introduced in March 1966, it had, not surprisingly, been rejected by Westmoreland and the MACV staff. Nor had it found many advocates elsewhere. Now it had one very important sponsor, Abrams himself. "The critical actions are those that occur at the village, district, and provincial levels," the study maintained. "This is where the war must be fought; this is where the war and the object which lies beyond it must be won." That object was the security and loyalty of the South Vietnamese people, the single-minded pursuit of which was to be the focus of the final years of American involvement in Vietnam.