This is the day. On the morning of October 17, 1967, an American infantry battalion walked into the three sided ambush that had been set for it the night before, and in about two hours it was destroyed. The Battle of Ong Thanh is one of the war's most haunting tragedies, and one of its ugliest cover ups. The unit was the Black Lions, the 2nd Battalion, 28th Infantry, led by Lieutenant Colonel Terry Allen Jr., son of a legendary World War II general. The day before, they had found a big enemy bunker complex and pulled back. Despite a company commander warning they did not have the men for it, Allen ordered a frontal assault for the morning. They marched almost straight into it. Over a thousand Viet Cong of the 271st Regiment had set a horseshoe ambush and simply let the Americans walk into the open end. When it sprang, fire came from three sides at once. The lead company was shattered in minutes. Colonel Allen was killed, along with every man in his battalion command group. In roughly two hours, 64 Americans were dead, 75 wounded. The forward artillery observer, Second Lieutenant Harold Durham, badly wounded and nearly blind from his injuries, kept calling fire onto the enemy swarming his own position until he was killed. He got the Medal of Honor. Among the other dead was Major Don Holleder, a former West Point football star who had flown to the edge of the battle and run forward through the fire trying to reach the trapped men. Then came the part that enraged the survivors forever. The Army announced Ong Thanh as a victory and claimed 101 enemy killed. The men who were there knew they had been ambushed and beaten. Decades later the journalist David Maraniss told the true story in They Marched Into Sunlight, and it stands as one of the clearest windows into the gap between what happened in Vietnam and what America was told.