Hu Tao: Severing Critical Routes

King Wu asked Grand Duke Jiang:
"When leading troops deep into enemy territory, we face a stalemate with opposing forces. The enemy has severed our supply routes and flanked us from the rear, attacking us from both front and back. If we engage in battle, victory seems unlikely; if we hold our position, we cannot endure long. What should we do?"

Grand Duke Jiang replied:
"To wage war deep in enemy lands, you must first master the terrain. Secure strategic positions—fortify your defenses with mountains, forests, natural barriers, and rivers. Guard passes, bridges, cities, and elevated grounds such as hill tombs. By doing so, your defenses will become impregnable. The enemy will neither cut off your supply lines nor outflank you to attack from both sides."

King Wu asked:
"When traversing vast forests, marshes, or open plains, if allied forces fail to arrive as scheduled and we suddenly confront the enemy, how should we act? If we attack, victory seems uncertain; if we defend, our position may crumble. The enemy surrounds our flanks and strikes our rear, plunging our army into panic. What then?"

Grand Duke Jiang answered:
"The essence of military command lies in advanced reconnaissance. When within 200 li (≈100 km) of the enemy, pinpoint their exact location. If the terrain disfavors us, advance with armored assault chariots to form mobile fortifications, supported by two rearguard units. Maintain a distance of 50 to 100 li (25–50 km) between the main force and the rearguard. This allows mutual reinforcement in emergencies. By adhering to this disciplined and adaptable formation, our army will remain invulnerable to defeat."

King Wu exclaimed: 

"Excellent!"