Before US troops entered the war, the Army had developed the operational terminology to describe the three basic types of operations conducted. The terms signaled the difference between the Vietnam War and previous American wars.

The first type of operation was "search and destroy."139 As is obvious from its title, operations of this type sought to locate the enemy and destroy him, and variations could be conducted from company to multidivisional level though the norm was probably a multi-battalion operation. No fixed model existed for such operations. "Horseshoes" could be formed by placing units in blocking positions, and ground thrusts could drive into the center of the horseshoe. Or, in a "hammer and anvil" operation, a blocking position could be occupied, and an attacking force could move toward it. Another variation included the emplacement of ambushes along likely avenues of escape. When an allied force moved into the area, escaping enemy units were ambushed as they attempted to flee. Straightforward attacks were also used. Ground forces often moved into enemy base areas, seeking contact and hoping to inflict heavy casualties on the enemy before he escaped.

In April 1968, the Army dropped the term "search and destroy" since it was, as General Westmoreland noted, "equated in the [American] public mind with aimless searches in the jungle and destruction of property."140 Other terms, such as combat sweep, reconnaissance in force and spoiling attack, replaced the term "search and destroy." But the original term was sometimes carelessly used in a blanket fashion to describe almost any kind of offensive operation.

Although "clearing" operations resembled search-and-destroy operations, they usually placed a greater emphasis on pacification. While search-and-destroy operations chased the enemy from an area or destroyed him, clearing operations kept him off balance and allowed the South Vietnamese government to extend its influence into the area.

Reconnaissances in force, combat sweeps or other offensive operations continued to be conducted, but the greatest emphasis in clearing operations was placed on eliminating local or main force enemy resistance and destroying his support base. Local commanders and political authorities, for example, often used cordon-and-search operations141 to "clear" a village or area. Thus, clearing operations usually lasted longer than search-and-destroy operations.