In retrospect, it is apparent that the North Vietnamese leadership underestimated the Americans almost as badly as America's leaders had underestimated them, and in November the North Vietnamese challenged the American buildup directly by sending PAVN regular battalions and regiments into combat against their American opposites. The result, in what came to be known as the Battle of the la Drang Valley, 14-16 November, 1965, was a major turning point of the war. In a bloody series of ambushes and counter-ambushes in difficult terrain near Plei Me in the Central Highlands, the 1st Air Cavalry Division and supporting air power inflicted severe casualties on the three PAVN regiments sent against it. The air cavalrymen suffered nearly as badly; the 2nd Battalion, 7th Cavalry Regiment-George Armstrong Ouster's old outfit overrun at the Little Big Horn-was nearly wiped out. But the North Vietnamese learned that American mobility and firepower could not be challenged in the open; they pulled back into remote base areas and settled down for the long haul. Westmoreland continued to go after them, sending his units on increasingly arduous search and destroy missions in difficult terrain, rejecting arguments by the Marines that their efforts would be better spent on pacification, winning the hearts and minds of the rural populace and forcing the communist main force battalions to come to them. This established the operational pattern of the war in South Vietnam for the next two years.
In the short term ROLLING THUNDER served its purpose. McGeorge Bundy's hopes, at least, were fulfilled; encouraged by clear evidence of American support, the ARVN began to fight with increasing skill and courage, holding things together until help could arrive. But the improvement was neither immediate nor universal, and the legacy of Diem's corruption and favoritism was still evident. In late May, three ARVN battalions were routed by the Viet Cong in a struggle for the village of Ba Gia near Quang Ngai, recapturing the village only weeks later with massive air support. Nor were persistent ARVN weaknesses the only problem with the American buildup: on 3 August, CBS correspondent Morley Safer accompanied a Marine patrol out of the Da Nang perimeter and observed Marines setting fire to the hamlet of Cam Ne on orders from their officers. The village may well have been Viet Cong controlled and the opposition more serious than Safer knew, but his cameraman's footage, broadcast on the evening news, of Marines setting fire to thatched huts over the weeping protests of old women and children left an image in American minds that was at variance both with the conduct expected of American troops and with what they had been led to believe about the nature of the war. The image proved impossible to eradicate. The credibility gap had achieved a new benchmark, extending beyond the press to the general public.
From the American military viewpoint, the essential structures in place by the end of 1965 remained essentially unaltered for the next two years. Things changed, but - at least in the eyes of those in charge - the changes were quantitative rather than qualitative. The scale of commitment increased from 184,300 American and 22,400 allied troops in South Vietnam at the end of 1965 to 485,600 U.S. troops and 59,300 allied by the end of 1967. During the same period ARVN strength increased from 514,000 to 798,000. At the same time, however, the PAVN presence in the south increased as well and, more to the point, there was no clear evidence that the guerrilla war - the all-important struggle for the hearts and minds of the rural populace - was going well. Debates raged within the American hierarchy over the percentage of villages that had been pacified, the numbers of communist regular soldiers and guerrillas in South Vietnam and the accuracy of body count figures. Secretary of Defense McNamara's penchant for providing support and allocating resources on the basis of hard, statistical data made the debates all the more intense. But in a fundamental sense, they missed the point, for in the final analysis war is more a matter of faith, determination and will than numbers.