What term describes the tactical use of an impenetrable barrier for protection?

The term that best describes the tactical use of an impenetrable barrier for protection is 'cover.' In tactical scenarios, cover refers to an object or structure that offers protection from gunfire, projectiles, or other threats. It allows individuals to shield themselves against potential danger while enabling them to maintain a position or return fire effectively.

Understanding the concept of cover is crucial in emergency situations, particularly in tactical environments or during active shooter incidents, as it directly impacts safety and response strategies. Unlike fortification, which typically involves the construction of barriers or strongholds over time, cover can be a temporary solution or any nearby object that provides immediate protection.