Du Fu, a great poet in the Tang Dynasty, wrote in his poem Before the Fortress: "Shoot the horse first, catch the thief first." Later generations borrowed the poem "Catch the thief first, then the king" as the name when compiling the "Thirty-six Plans", which means to catch the main enemy first in battle and the key first in doing things. In the ancient military history of China, there was a famous war case "Zhang Xun's shooting at Yin", which was a model of "catching thieves and capturing the king".

In 755 AD, due to the fatuous corruption and political darkness in the late Tang Xuanzong, the "Anshi Rebellion" broke out. Rebels in the Anshi Rebellion quickly occupied Chang 'an, Tang Dou, and Emperor Xuanzong was forced to take refuge in Sichuan. In order to occupy the whole country and attack south, the insurgents were held back by the guarding generals Zhang Xun and Xu Yuan in Suiyang (now Shangqiu, Henan) for nine months, which is called "Suiyang Defence War" in history.

Zhang Xun statue, located in Zhang Xun Temple, Shangqiu, Henan.

At that time, Yin, the leader of the rebel army, led a hundred thousand troops to besiege Suiyang. Zhang Xun used the tactic of "exhausted soldiers". Whenever the rebels are ready to rest at night, they order their soldiers to beat drums and shout, creating the illusion of attacking. After a few nights, the rebels were exhausted and finally fell asleep. At this time, Zhang Xun really launched an attack, and the dispatching department rushed out of the city and killed the rebels by surprise. The rebels woke up from their dreams, panicked and made a mess.

Zhang Xun knew the truth that "the thief gets the king first". However, because Zhang Xun didn't know Yin, he couldn't find him in the army at the moment. Zhang Xun thought of a plan and ordered the soldiers to sharpen the straw as an arrow and shoot at the enemy. After being shot by an arrow, the rebels found themselves unhurt. When they saw that it was actually a straw, they thought there were no arrows in the patrolling army, so they had to use straw as a substitute. They were overjoyed and reported to the leader Yin. In this way, Zhang Xun recognized Yin in the crowd at a glance and immediately ordered the archer Nanji (Ji) Yun to shoot an arrow. Nan Jiyun fired an arrow and hit Yin's left eye. Yin ran away, covering her eyes, and the rebels' morale was in chaos, and they fled in succession.

"Catch the thief and capture the king" is of great significance in military strategy, because the leader or core figure is the hub and key for the organization to exert its strength. Therefore, to destroy and disintegrate an organization, we must focus on attacking its leaders and core figures. Ming Yingzong, the emperor of the Ming Dynasty, was captured by the Walla army, which wiped out hundreds of thousands of troops. In World War II, Hitler, the leader of German fascism, committed suicide, and the Germans completely surrendered to the Allies. These are all examples of "catching the thief and catching the king".