Which principle of war emphasizes concentration of forces at the decisive point?

The principle that emphasizes the concentration of forces at the decisive point is mass. This principle highlights the importance of rallying the greatest possible combat power at the critical moment and place to achieve a decisive effect on the enemy. By consolidating forces, a commander can increase the chances of success by overwhelming the enemy at a specific point in time and space.

Mass allows for the sheer weight of numbers and resources to be leveraged against an adversary, making it a crucial element in military strategy. When forces are effectively massed, they can exploit weaknesses in the enemy's defenses, creating opportunities for victory that might not be possible if forces were dispersed. This principle plays a vital role in planning and executing operations, ensuring that resources are aptly allocated to maximize impact at key moments.

The other principles, while essential in their own right, do not specifically address the focus on concentration of forces like mass does. Each principle contributes to successful military operations, but mass distinctly emphasizes the power of concentration at decisive moments.