Which element is not part of a defensive operation?

In a defensive operation, the primary focus is on protecting and holding a position against enemy forces, which involves several key elements that are integral to its success. Mass and concentration leverage forces effectively to enhance combat power where needed. Operational security ensures that the enemy cannot gather information that could undermine defensive positions. Flexibility allows the defending force to adapt to changing circumstances on the battlefield, which is critical in maintaining effectiveness in defense.

Ambush tactics, while useful in various combat situations, are not a central element of a defensive operation. Instead, they are typically associated with offensive operations or specific tactical engagements aimed at taking advantage of enemy movements rather than maintaining a defensive posture. Effective defense relies more on strategic positioning and control of terrain, making ambush a complementary tactic rather than a foundational characteristic of defensive operations.