Which principle ensures that machine gun firing positions are not easily identified by the enemy?

The principle that ensures machine gun firing positions are not easily identified by the enemy is defilade. When a position is in defilade, it means that it is located in a way that provides cover from enemy observation and fire, typically by using terrain features such as hills, ridges, or other natural barriers. This obscures the position from direct view, making it more difficult for the enemy to pinpoint the location of the machine guns.

Using defilade effectively allows for a surprise element in firing, as the enemy may not know where the fire is coming from, and it minimizes the risk of the firing position being targeted by return fire. The terrain advantage protects both personnel and equipment in that position, enabling them to engage the enemy while remaining concealed.

Other principles such as interlocking, economy, and protection serve different purposes in a combat scenario but do not specifically address the concealment of firing positions from enemy observation in the same manner as defilade does. Interlocking positions involve creating overlapping fields of fire to enhance coverage against targets, economy pertains to resource management in a broader tactical sense, and protection involves measures to shield forces or equipment from attacks.