Final answer:
The principle of war that utilizes the security principle by catching the enemy unprepared is the principle of surprise. It relies on deception, unpredictability, and strategic planning to achieve an advantage over the enemy and can lead to decisive victory with efficient resource use.
Step-by-step explanation:
The principle of war that leverages the security principle by attacking the enemy at a time, place, or in a manner for which they are not prepared is known as the principle of surprise. Employing surprise is a strategic method to gain a significant advantage over the enemy. It involves attacking the enemy when they least expect it, which could mean during a time they are not ready, at a location they have not fortified, or in a way they have not anticipated.
This approach is founded on the concept that all warfare is based on deception and the importance of being ready to attack while making the enemy believe you are not in a position to do so. It requires careful planning, gathering of intelligence, and the element of unpredicted action, thus compelling the adversary into a position of vulnerability. By doing so, it maximizes the attacking force's effectiveness while minimizing the enemy's ability to respond effectively.
It is clear that through the proper application of this principle, combined with other factors of warfare such as strength, strategy, and unity, a force can achieve a decisive victory, often with a minimal expenditure of resources and lower risk to its own forces.