The captured soldier got two things out before the shooting started. The Americans had come down in the middle of a way-station on the trail, he said, and there were more than a thousand of his comrades in the trees around them. A volley of fire ended the interrogation and mortally wounded the troop commander, Captain John Sabine. It was the afternoon of 30 March 1966, five kilometres south of the Chu Pong Massif, and twenty-eight men of the 1st Cavalry Division had just landed on top of a regiment.
Operation Lincoln began on 25 March 1966 with a simple premise: find the enemy's base areas in the western highlands before the monsoon arrived and made them impossible to reach. Intelligence pointed at the country around Duc Co, Plei Me and Thach An - the broken, forested ground between Pleiku and the Cambodian border, where the People's Army of Vietnam and the Viet Cong were assumed to be stockpiling for a wet-season offensive.
The opening moves were pure logistics. Company B of the 1st Battalion, 69th Armored Regiment and Troop C of the 3rd Squadron, 4th Cavalry pushed out along Highway 19 to hold the road from the Mang Yang Pass to Landing Zone Oasis, which would serve as forward headquarters for Colonel John J. Hennessey's 1st Brigade. With the highway open, the brigade headquarters and two more battalions drove down from Camp Radcliff. C-130s put the 1st of the 12th Cavalry into Duc Co Camp; helicopters lifted the 1st of the 8th Cavalry to Landing Zone Bear, ten kilometres southeast of it.
From 26 to 29 March the two infantry battalions swept west to the Cambodian border and south into the northern reaches of the Ia Drang Valley. They found almost nothing: a handful of small, inconclusive contacts, the kind of thing that produces expended ammunition and no information.
The ground itself carried a heavy memory. The previous November, the same division had fought the Battle of Ia Drang in the shadow of the Chu Pong Massif, and both armies had spent the winter drawing lessons from it. The massif still sat there on the western skyline, a tangle of forested ridges and valleys running across the Cambodian border, hiding whatever it chose to hide. That same March, American aircraft were firebombing its canopy with napalm under a separate effort, Operation Hot Tip, trying to burn away the cover.
On the afternoon of 30 March, scout helicopters of Troop B, 1st of the 9th Cavalry caught three PAVN soldiers in the open five kilometres south of the massif. They fired, and roughly thirty more men broke from the undergrowth. Troop A - twenty-eight soldiers - went in by helicopter just south of the sighting, three squads moving northeast while the fourth held the landing zone.
The prisoner they took belonged to the 18B Regiment, which had only just come down the Ho Chi Minh Trail. His answer cost him twice: first when the fire that mortally wounded Captain Sabine cut short his questioning, then when the helicopter carrying him out was shot down nearby and he died in the wreck.
What followed was arithmetic under fire. Fifteen cavalrymen were still on the ground. A helicopter came in that could not lift them all, and three men volunteered to stay. The overloaded aircraft got airborne, took hits, and crashed, killing all but two aboard. Another helicopter went back for the three who had stayed and brought them out.
Half a kilometre southwest, Company A of the 1st of the 12th Cavalry landed unopposed at Landing Zone Eagle and started northwest. Concealed machine guns opened on them, wounding the company commander and killing the executive officer, and the company fell back to the landing zone under gunship cover. When a CH-47 came in to pull them out, it was hit and went down inside the perimeter.
So the Americans dug in around a wrecked Chinook and waited for morning. At 01:30 two supply bundles came down and the company recovered one. Nine kilometres east, Company A of the 1st of the 8th Cavalry and Battery A of the 2nd of the 19th Artillery had built a firebase, and its shells walked around the perimeter through the dark alongside air strikes. No assault came. The North Vietnamese pulled out in the night, and at first light the cavalrymen counted 197 of their dead around the position - men from a regiment that had come the length of the trail to reach this hillside.
On 31 March the whole 1st Brigade shifted south of the Chu Pong Massif to work the battlefield and chase stragglers. General Harry Kinnard added the 3rd Brigade under Colonel Hal Moore, who had led the 1st Battalion, 7th Cavalry at Ia Drang in November, and put the 3rd Brigade of the 25th Infantry Division under 1st Cavalry control. Three brigades then combed the massif. Gunships caught men retreating toward Cambodia; nothing larger developed.
Operation Lincoln closed on 8 April. The final tally recorded 477 PAVN dead with a further 232 estimated, against 43 Americans killed. By the standard applied at the time it was a success: a monsoon offensive disrupted, a regiment scattered before it could be used. What a ledger cannot record is that almost all of the fighting in two weeks came down to a single afternoon, decided by men on both sides who had no idea, until the shooting started, what they had walked into.
The article's marker sits at 13.983 N, 108.000 E, on the outskirts of Pleiku, but Operation Lincoln was fought out to the west. Landing Zone Oasis lay southwest of the city, and Duc Co Camp sat on QL-19 about 55 km west of Pleiku, 13 km short of the Cambodian border; the 30 March action took place near the Chu Pong Massif, the forested upland straddling the border in Chu Prong district, above the Ia Drang Valley. Terrain runs 700-800 m on the plateau, falling and roughening westward into hill country and dense canopy. Pleiku Airport (PXU / VVPK, field elevation 744 m / 2,441 ft) is the practical base for a look; Buon Ma Thuot (BMV / VVBM) lies 181 km south. Fly the Ia Drang line at 2,000-4,000 ft AGL to read the ground the way the scout crews did - the valley floors, the tree lines, the clearings big enough for a Huey. Dry season from about November to April gives the best visibility; the southwest monsoon between roughly May and October closes the valleys with cloud and rain, which was precisely the point of the operation.