What is the primary purpose of the 'screen' mission in defense?

The primary purpose of the 'screen' mission in defense is to provide early warning and reconnaissance. This type of operation involves forward elements being positioned to observe enemy movements and gather critical information about their intentions. By doing so, the defending force can make informed decisions about troop movements and defensive actions, ensuring that they can respond effectively to any threats. A screen allows for early detection of an advance, enabling the main body to prepare for battle or to reposition as necessary.

While engaging the enemy directly, holding the enemy in position, or protecting vital assets are all important tactical objectives, they are not the central focus of a screening mission. A screen's effectiveness relies on its ability to maintain a safe distance while still providing essential intelligence, making early warning and reconnaissance its primary goals.