Final answer:
Commanders ensure a mission's success by continually assessing and adapting to the enemy's movements, maintaining troop discipline and morale, and making strategic decisions even under harsh conditions.
Step-by-step explanation:
Commanders continually assess and adapt their strategies to ensure the mission's success. They must remain vigilant, adapting to the enemy's movements and intentions, maintaining discipline and confidence within their ranks, and making decisive, often difficult, choices that will lead to victory even in dire circumstances. For instance, placing troops in challenging positions might inspire greater tenacity and commitment to the mission, as suggested by principle 58 that indicates troops will survive deadly peril and emerge safely from desperate straits.
Additionally, commanders engage in intelligence gathering, as noted in principle 20, understanding the importance of knowing the enemy's key personnel. Training and discipline, such as reinforcing commands (principle 44) and displaying confidence in soldiers (principle 45), are critical for an effective military force. Furthermore, the ability to adapt to changing circumstances, as indicated in the Vietnam example, shows the necessity for alignment of orders with overarching strategic objectives.