Vietnam by Nigel Cawthorne Page B

to harassing fire and the planting of mines. By this time 159 Marines were dead and 345 wounded. The NVA body count stood at 1,290, though their bodies were so badly mutilated that their casualties had to be estimated from the number of water bottles left on the battlefield.
    The NVA then began lobbing shells over the DMZ using 152mm howitzers, which out-ranged any field artillery the Marines had. The tiny firebase of Con Thien perched on top of the Hill of Angels was only big enough to accommodate one reinforcement battalion. It took at least 200 rounds incoming a day during September: on 25 September alone, it took 1,200 rounds. Under this bombardment, the NVA made repeated attacks in force. On 4 September, Marines just a mile south of Con Thien had to be relieved by tanks. A similar action on 7 September left fourteen Marines dead. The NVA 812th Regiment, reportedly wearing USMC helmets and flak jackets, swept around to the southwest on 10 September, knocking out a Marine flame tank and a gun tank with rocket-propelled grenades. Thirty-four Marines were killed and 192 were wounded.
    The NVA moved against Con Thien itself on 13 September, but were driven back. Anticipating another attack, two more Marine battalions were moved up. For seven days, they suffered a furious pounding with mortars and artillery. When they finally went on the attack, they ran straight into the 90th NVA regiment and called in tanks, but the previous 96 hours of rain meant that the tanks could not reach them. Eventually the weather became so bad that the battle for Con Thien became an artillery battle. From 19 to 27 September, more than 3,000 mortar and artillery rounds hit the hill fort. The American response was one of the greatest concentrations of firepower in support of a single division in the history of warfare. US field units fired 12,577 rounds at enemy positions, with the 7th Fleet contributing 6,148 more. Eventually, NVA activity eased off, but the Marines continued to find new bunkers and trench complexes around the perimeter. The enemy barrage did not cease and the Marines began to call the Hill of Angels 'the meatgrinder'.
    With Con Thien more or less in American hands, the construction of the McNamara Line went ahead. Building a defensive barrier along the DMZ had been the idea of Robert Fischer at the Havard Law School. He had sent a memo outlining the concept to McNamara. General Westmoreland dismissed it. He disliked the idea of static defence on principle, as did Admiral Ulysses Grant Sharp Jr, commander of the Pacific Fleet, who did not like the plan either. But McNamara called together a group of top academic scientists known as the Jasons, after Jason and the Argonauts, who also took a mythological trip into uncharted territory, to assess its feasibility. They met in the summer of 1966 in the cloistered atmosphere of Dana Hall, a secluded prep school for girls in Wellesley, Massachusetts. The initial suggestion was a line 160 miles long and ten miles wide made of stretches of barbed wire and studded with mines, chemical weapons, and sensor devices, interspersed with huge free-fire zones that had been denuded of forest cover.
    The Jasons figured that a sixty-mile long fence could be built within a year. It would be protected by 'gravel mines', three-inches square, that would explode when they were stepped on or run over by a truck. Smaller 'button mines' the size of an aspirin would blow off a finger or a toe. Any explosion would be picked up by acoustic sensors, which would be monitored by patrol aircraft flying overhead who would drop cluster bombs, containing baseball-sized bomblets. The Jasons reckoned that 240 million gravel mines, 300 million button mines, and 120,000 cluster bombs a year would be needed. The cost: $1 billion.
    Unfortunately, no mines could be found that could tell the difference between a human being and a wild animal: Vietnam engagement reports are full of incidents where air strikes were called down on