Operation Attleboro is launched in War Zone C - Sep 14, 1966 - HISTORY.com

U.S. II Field Force initiates Operation Attleboro with an attack by the 196th Light Infantry Brigade against Viet Cong forces near the Cambodian Border in War Zone C (near Tay Ninh, 50 miles northwest of Saigon in III Corps Tactical Zone).

When the communists appeared to want to make a fight of it, the U.S. commander, Lt. Gen. Jonathan Seaman, sent in reinforcements from the U.S. 1st Infantry Division; the 173rd Airborne Brigade; a brigade each from the U.S. 4th and 25th Infantry Divisions; and a contingent from a South Vietnamese division. Before the operation was over, more than 20,000 U.S. and South Vietnamese troops were involved, making it the largest operation at that point in the war. After more than six weeks of hit-and-run fighting, the Viet Cong forces sustained 1,106 casualties and fell back to sanctuary areas in Cambodia.

Operations like Attleboro, and others to follow such as Cedar Rapids and Junction City, were examples of the search and destroy tactic dictated by Gen. William Westmoreland, commander of U.S. Military Assistance Command Vietnam (MACV), the senior American headquarters in Saigon. The objective was to find the Viet Cong and engage them in decisive battle; the problem was that the communists often refused to engage in the type of set-piece battles for control of critical terrain that had been the norm in previous wars, like World War II. Westmoreland’s search and destroy tactic led to a war of attrition in which battles were fought often over the same territory again and again and where each side inflicted as many casualties as possible on the other. This approach was criticized because it meant that the war would go on as long as the communists were prepared to accept and replace their losses on the battlefield.