by Neil Sheehan
U.S. Grant Sharp, Commander in Chief Pacific, might be a seafaring warrior, but he believed in air power, and the air campaign against the North was his war. (Westmoreland did not control air operations outside of South Vietnam.) In the flush of March 1965 the admiral described how aerial interdiction would master the Vietnamese in an “LOC cut program” he and his air staff devised for the “Panhandle” section of North Vietnam from the 20th Parallel down to the DMZ. LOC is the military abbreviation for lines of communication, i.e., roads, rail lines, and waterways. The planes were going to bomb “choke points”—bridges, ferry crossings, and spots where the roads and rails curved around slopes and headed through passes. Repeat strikes and free-ranging “armed reconnaissance” round-the-clock, at night by flares, would prevent the Vietnamese from making adequate repairs. “All targets selected are extremely difficult or impossible to bypass,” Sharp said in a cable to the Joint Chiefs. “LOC network cutting in this depth will degrade tonnage arrivals at the main ‘funnels’ and will develop a broad series of new targets such as backed-up convoys, off-loaded matériel dumps, and personnel staging areas at one or both sides of cuts.”
In 1965, in 1966, in 1967, and in the years of the air war to follow, the planes of the U.S. Air Force and the Navy did not destroy more than 20 to 25 percent of the trucks rolling down the Panhandle and along the Trail through Laos to sustain the battlegrounds of the South. The Vietnamese also managed to keep their railroads operating, although at times they had to resort to using sections of the lines as cargo shuttles for the trucks. If one decided that this tally of trucks destroyed was too conservative and added another 10 percent, the Vietnamese still got two-thirds of the weapons and ammunition and other provender of war to its destination, a satisfactory “through-put” rate, in the jargon of the logisticians. The average loss to aircraft of troops sent to the South was much less than 20 to 25 percent, because the men marched through the most dangerous areas to better avoid the planes. An infiltration group tended to lose about 10 to 20 percent of its men along the way, but mainly from sickness and desertion.
Airmen have never been able to wage a successful interdiction campaign, because they are confronted with an insoluble dilemma. It is composed of time and distance compounded by weather, antiaircraft defenses, and the ingenuity and determination of those other human beings on the ground whom they are trying to kill. If Italy and Korea exposed the dilemma, Vietnam illuminated it with unprecedented drama, because the dimensions of the challenge were so much greater there. The insurmountability of time and distance starts with the practical consideration that the number of planes is always limited and so is the time they can stay in the air. In 1967, when Admiral Sharp had his war in full flight, the United States could put about 300 strike aircraft over North Vietnam and Laos on an average day and keep each there an average of approximately half an hour. The Vietnamese transportation network ran all the way down from the China border. With a limited number of planes and a limited time to strike, it was impossible to subject enough of the roads and rail lines to surveillance and attack a sufficient number of hours in twenty-four to have a decisive impact. A lot of the trucks escaped simply because no aircraft happened to be overhead while they were moving. Indochinese weather worsened the time and distance problem by forcing planes to sit idle at airfields and on the decks of carriers when they should have been striking, and then often limited what the pilots could see when they were on the attack. The weather hampered the Vietnamese too. For a number of years they lacked enough all-weather roads to keep the Trail open during the Laos monsoon season from May to October.
The Vietnamese further degraded American air power with the superlative air defenses they established with Soviet-supplied early-warning radars, antiaircraft cannons, and SA-2 missiles (surface-to-air, called SAMs by the pilots), and by passing out semiautomatic and automatic weapons to everyone in the countryside able to shoot at a plane. To survive, the pilots had to bomb and strafe from higher altitudes where they were less accurate. They had to waste precious “time over target” dodging missiles. The defenses also did not have to shoot down fighter-bombers to effectively reduce the number. Planes that might have been hitting transportation targets were instead absorbed in going after the SAM sites and antiaircraft batteries in order to try to protect their bomb-laden fellows. More than 40 percent of the sorties flown over North Vietnam and Laos were consumed in such “flak suppression” missions and other escort duties.
What the Vietnamese did with head and hand was the greatest compounder of the time and distance problem. The Communist leaders marshaled a force of 300,000 men and women to labor full-time at repairing the roads and rails and bridges and at continuously expanding the network. Another 200,000 North Vietnamese peasants worked in what time could be spared from the fields. The Chinese came to the assistance of the Vietnamese with roughly 40,000 engineer and antiaircraft troops to help keep open the two rail lines from the border to Hanoi. The Russians provided bulldozers for the road crews. The principal earth-moving equipment was a type more familiar in Vietnam—pick and shovel, a wheelbarrow that rolls better than the American model because it has bicycle wheels on the sides, and if no wheelbarrow was available to move earth, then two baskets, one slung at each end of a pole balanced on the shoulder.
An American thinks of a road or trail as a line going from Point A to Point B, curving only as necessary to accommodate terrain. The Vietnamese wanted a “chokeproof” road system, so they built six or eight or ten different routes from A to B, often with pontoon bridges at the crossing points which were removed at dawn and towed back into place at dusk. When the planes cut a road by cratering it with bombs or knocked out a bridge, the trucks shifted to an alternate route while repairs were carried out. The multiplicity of routes also permitted the convoys to make themselves scarcer targets by dispersing. The drivers camouflaged their trucks with foliage, of course, and there were pull-off points everywhere in which they could hide at an aircraft alert. The Vietnamese camouflaged long stretches of road too. They tied the trees together overhead or suspended big trellises of bamboo covered with brush and freshly cut boughs.
The pilots exacted punishment. Driving a truck year in year out with 20 to 25 to perhaps 30 percent odds of mortality was not a military occupation conducive to retirement on pension. A man or woman on a road crew could have an assignment as dangerous as an infantryman’s. To keep the roads open, the crews had to stay close to them, closest of all to the segments most frequently bombed. Bombs that missed trucks and bridges hit people. The crews were caught in the flares of night raids. It was impossible for them to do their job and shift as often as they should have to avoid the carpets laid by the B-52S in Laos and the Panhandle of North Vietnam. The memorial cemetery to those who died for the Ho Chi Minh Trail was to cover almost forty acres and to hold the headstones of 10,306 Vietnamese men and women. Their names had been recorded. Thousands of others who died for the Trail were to remain where they perished, unnoted in the confusion of war.
To punish was not to prevail. Each double loop and triple bypass in this ever enlarging whirligig of roads that must have been difficult to keep track of after a while even at the transport center in Hanoi meant more road mileage the American pilots had to cover. The Ho Chi Minh Trail was the best example of the achievement of the Vietnamese. The straight-line length of the Laos corridor from the Mu Gia Pass at the top to the triborder point at the bottom where Laos, Cambodia, and South Vietnam meet is about 250 miles. The Vietnamese estimated that when finished the Trail comprised about 9,600 miles of all-weather and secondary roadway. The biggest portion of the web work was within this 250-mile corridor.
Oley Sharp and the Joint Chiefs told McNamara and the president that they could stop the trucks by shutting off most of the gasoline. All they had to do was to bomb the principal tank farm at the port of Haiphong and the other bulk POL storage facilities, mainly in the Hanoi-Haiphong area. Walt Rostow, who replaced McGeorge Bundy as Johnson’s special as
sistant for national security affairs in 1966, was also enthusiastic about the scheme from his World War II experience recommending targets for the strategic bombing of Germany.
The sky was clear over Haiphong on June 29, 1966. The pilots left the receiving facilities and the tank farm in flames. Within a month, nearly 80 percent of the known bulk POL (petroleum, oil, and lubricants) storage capacity of North Vietnam was gone, including a number of small sites that were harder to hit. As far as can be determined, not a single truck ran out of gas. Rather, the number of Russian-model trucks supplied to the Vietnamese by the Soviet Union, the Eastern European countries, and China kept rising through 1966 and by the end of the year there were twice as many as in 1965. The Vietnamese, who produced no oil and refined no gasoline themselves, anticipated the raids and long before had dispersed enough gasoline, diesel fuel, and lubricating oil to meet their needs in underground tanks and in concealed stacks of barrels. In the future they had the Russians ship them much of the POL poured into barrels ahead of time so that they could disperse it immediately on arrival. To facilitate refueling the trucks, they began the construction of two pipelines down the Panhandle and into Laos, with spur lines branching off as useful. Three of the spurs were eventually to reach into South Vietnam, one down the A Shau Valley in the mountains west of Hue. One of the commemorative statues in the memorial cemetery of the Ho Chi Minh Trail was to be a figure of a woman operating a gasoline pump.
Krulak showed prescient wit when he warned in his December 1965 strategy paper that trying to interdict columns of men and supplies moving to the South “can be likened to fighting an alligator by chewing on his tail.” That Sharp and the carrier admirals and Air Force generals under him would consent to preside over this phantasmic enterprise was a study in how obsession and ambition can warp judgment. The “truck kill” was the central measure of the effectiveness of interdiction in the air war. Year after year, Sharp and his senior air commanders traded complicated jets that, depending on the type, cost the American taxpayers from $1 to $4 million each (the rough equivalent of $3 to $12 million in 1985 dollars), and brave airmen in whom hundreds of thousands of dollars and the faith of the nation had been invested, for the Russian version of two-and-half-ton trucks and Vietnamese drivers who were born with their courage and whose education in plane dodging was acquired on the job. A number of trucks destroyed for every plane shot down over the North did not improve the exchange. The trucks cost about $6,000 apiece to make, in the estimate of the Defense Intelligence Agency, and were one of the items the heavy industry of the Soviet Union and Eastern Europe happened to produce in abundance, and that China also manufactured in sizable quantity. It was a comparatively minor expense to replace every truck lost and to oblige the Vietnamese by simultaneously increasing the convoy fleet. In a report to the Joint Chiefs at the end of 1967, Sharp made an admission that was remarkably honest under the circumstances. He admitted that after another year of bombing there were just as many trucks in December as there had been in January. There probably were more. The number of trucks sighted in Laos during 1967 showed a 165 percent increase over those seen during 1966. Robert McNamara estimated in 1967 that the Vietnamese had 10,000 to 12,000 trucks coursing the roads.
The solution did not lie in closing Haiphong and the other ports of the North with mines and bombs, as Krulak and Greene thought and as Sharp and Greene’s fellow members of the Joint Chiefs now increasingly clamored to do. Closing the ports appeared to be the answer because, except for food and lives, practically all the essentials of the war came from Russia and Hanoi’s other Communist allies; the bulk arriving by sea. Freighters just happened to be the most convenient means of transport. China was willing, with its foreign-policy goals of the moment, to permit the Soviets to transship equipment and supplies to the Vietnamese on Chinese railways. Had the ports been shut the Vietnamese would have brought the weapons and other essentials down from the China border by rail and truck, as they were to do after Nixon belatedly closed their ports in 1972. They made arrangements for such transshipment in the spring of 1967, and some Soviet supplies began coming through China by rail that year.
The foolish expectations of the POL raids in the summer of 1966 upset McNamara so much that he was able to discern the truth. He warned Johnson that the only way they could achieve decisive results with the air war was to target the people of North Vietnam. “To bomb the North sufficiently to make a radical impact upon Hanoi’s political, economic and social structure, would require an effort which we could make but which would not be stomached either by our own people or by world opinion; and it would involve a serious risk of drawing us into open war with China,” he told the president in a memorandum that October.
Dan Ellsberg helped to disabuse McNamara of his illusions about the ground war in the South. Ellsberg remembered the moment as “the height of my bureaucratic career.” It occurred that same October of 1966 aboard a “McNamara Special” bound for Saigon, one of those windowless KC-135 jet tankers the Air Force had fitted out for longdistance VIP travel and that the secretary used on his frequent shuttles. Nicholas Katzenbach was along on his first trip to Vietnam as the new under secretary of state. Porter had sent Ellsberg to Washington to brief Katzenbach and to travel with him as his escort officer.
The seats in the nonsleeping section (there were separate compartments with cots so that the VIPs could arrive refreshed) were arranged around desk-tables at which one could eat a meal or work. Ellsberg happened to be seated across the aisle from his former Pentagon superior, John McNaughton, McNamara’s deputy for foreign affairs. McNamara was sitting on the opposite side of the table from McNaughton. Not without calculation, Ellsberg had brought along a briefcase full of his best memos, more than 200 pages of them, including a vivid account of the three days he had spent with Vann in Hau Nghia in the fall of 1965. As soon as the plane lifted off from Andrews Air Force Base he opened the briefcase and passed a memo to McNaughton with the suggestion that he might find the reading interesting enough to while away flight time. McNaughton glanced through the memorandum and handed it to McNamara, who looked at it and then began to read. Ellsberg fetched another memorandum from the briefcase for McNaughton, who started to read carefully too.
McNamara and McNaughton were both swift readers, and Ellsberg had emptied his briefcase before the plane had gone far toward Saigon. McNaughton called him aside a bit later and said that McNamara wanted a copy of the Hau Nghia memo, the best official writing Ellsberg was to do in Vietnam, rich in detail of the moral depravity and buffoonery of the Saigon side. McNamara had another request, McNaughton said. In the interest of maintaining civilian-military relations, would Ellsberg please not show this memorandum to General Wheeler.
Disaffection, once begun, acquires a momentum of its own, and by now more than the failure of the air campaign was at work on Robert McNamara. The sudden receptivity to realities he had ignored for years was what apparently led him that fall of 1966 to approve the proposal by Alain Enthoven, the chief of his Pentagon brain trust, the Office of Systems Analysis, to hire Vann as the head of the new Asian Division that Systems Analysis was forming. McNamara’s report to the president on his October 1966 trip to Vietnam was a watershed. The McNamara of just a year earlier could absorb the shock of 230 Americans dead in four days of fighting in the valley of the Drang and urge the president to “stick with” Westmoreland’s war and “provide what it takes in men and matériel.” Now he wanted to put a clamp on Westmoreland, to end “the spectre of apparently endless escalation of U.S. deployments.” The general should be told he could have a total of 470,000 men and no more. Where the air war in the North was concerned, McNamara no longer had any stomach for the blackmail of bombing pause and ultimatum and escalation. He wanted Johnson to try to coax the Vietnamese Communists into negotiations by halting the bombing in all of North Vietnam, or if the president thought that too generous, in the northeast quadrangle—the Hanoi-Haiphong region up to the China border. The Joint Chiefs made it c
lear they would revolt if the president did anything of the kind.
McNamara was beginning to learn, and the more he learned the more disturbed he became. Although Enthoven had been unable to hire Vann, he did hire as an analyst in 1966 a young statistician named Thomas Thayer who had spent two and a half years in South Vietnam working for the Pentagon’s Advanced Research Projects Agency. McNamara started to get a stream of what he understood, numbers, and these were the right numbers about the war, the kind McNamara had not been in a mood to heed when Krulak had earlier sought to rouse him with them. Thayer’s own experience in Vietnam had taught him what mattered, and he was wise enough to test his statistical findings against the reflections of canny fighters whose analyses had been distilled from the battlefield. He interviewed Hal Moore after Moore relinquished command of the 3rd Brigade of the Air Cav and came to Washington in the fall of 1966 to serve as a staff assistant to McNaughton. Moore was convinced that one of the reasons the Vietnamese had struck the Cav so boldly and repeatedly at the Drang and had resisted so ferociously at Bong Son was that they had been intent on learning how to fight the Americans. They had learned, Moore said, and moreover had got the Americans to fight the war their way. They were leading the Army and the Marine Corps by the nose.
In the spring of 1967, when the insatiable general in Saigon wanted still more troops, this time his “Minimum Essential Force” of 550,500 Americans by mid-1968, or an “Optimum Force” of 678,000 if the president wished to hasten victory, Thayer was ready. He and a staff of analysts he had assembled within Systems Analysis in a special Southeast Asia Office had done sufficient research to demonstrate that Westmoreland’s war of attrition was an absurdity. Enthoven transmitted the findings to McNamara with his memoranda urging the secretary to oppose any troop increase beyond the ceiling of 470,000 men.
