Avoid Strength, Attack Weakness

Besiege Wei To Rescue Zhao

Means that you must avoid your enemy's strength when he's too strong, but attack it's weakness. You can win without wasting your power by useless attacks to your enemy. That leads to an easy victory.

When the enemy is too strong to attack directly, then attack something he holds dear. Know that in all things he cannot be superior. Somewhere there is a gap in the armour, a weakness that can be attacked instead.

It is wiser to launch an attack against the enemy forces when they are dispersed than to fight them when they are concentrated. He who strikes first fails and he who strikes late prevails.

Warring States Era China

This strategy derives its name from a famous incident that occurred in 354 BC.

At this time one of China's most renowned strategists, Sun Bin (A descendent of the even then famous Sun Zi) was an advisor to the king of Qi. Sun had earlier been at the court of Wei but another minister, Pang Juan, became jealous of Sun's cleverness. Through court intrigues he had Sun framed as a spy, sentenced to mutilation, and imprisoned. Sun escaped and fled to Qi.

Several years later the king of Wei appointed the same Pang Juan as commander of the army and sent him to attack the capital of Zhao. The king of Zhao immediately appealed to Qi for help. The king of Qi consulted his advisors who all spoke in favour of rushing to aid their ally, only Sun Bin recommended against attacking. Sun advised: " To intervene between two warring armies is like trying to divert a tidal way by standing in its path. It would be better to wait until both armies have worn themselves out." The king agreed to wait.

The siege of Zhao had lasted more than a year when Sun Bin decided the time was ripe to come to Zhao's aid. The king of Qi appointed prince Tian Ji as general and Sun as military advisor. Tian Ji wanted to attack the Wei forces directly to lift the siege of Zhao, but again Sun advised against direct intervention saying: " Since most of Wei's troops are out of the country engaged in the siege, their own defence must be weak. By attacking the capital of Wei, we will force the Wei army to return to defend their own capital thereby lifting the siege of Zhao while destroying the Wei forces in turn." Tian Ji agreed to the plan and divided his army into two parts, one to attack the capital of Wei, and the other to prepare an ambush along the route to the capital.

When the Wei general Pang Juan heard that the capital was being attacked, he rushed his army back to defend the capital. Weakened and exhausted from the year long siege and the forced march, the Wei troops were completely caught by surprise in the ambush and suffered heavy losses. Chao was thus rescued while Pang Juan barely escaped back to Wei to recoup his losses. Sun Pin would later defeat his nemesis Pang Juan using another classic strategy.

This stratagem originates from the Warring States period. In 354BC, the king of Wei sent general Pang Juan to attack Handan, the capital of Zhao. Wei laid siege to Zhao for a year. Both Zhao and Wei's troops became weakened and exhausted.

The king of Qi was approached by Zhao for help and he decided to send his troops to save Zhao.Tian Ji was appointed as commander and Sun Bin as military advisor.

Tian Ji ordered the troops to go to Handan directly to relieve Zhao. But Sun Bin stopped him saying, "Trying to help Zhao during a siege is like trying to unravel a tangled knot, and sending troops to Handan is like using a fist to unravel the knot. We're unlikely to suceed. To mediate between two fiercely contending parties, one must not intervene directly by joining the fray."

"Now that Wei's crack troops are outside its territory, its own defence must be weak. If we make an all-out attack on Wei, its troops in Zhao will be force to rush back to defend Wei.

Tian Ji took Sun Bin's advice and made a diversionary attack on Wei's capital Daliang coupled with an ambush along the mountain pass at Guiling which Pang Juan's troops had to go through on their return journey to Wei.

The worried Wei troops made haste to return to their capital and in the process wore themselves out. Wei's troops fell for the ambush at Guiling. The exhausted troops were completely routed. Pang Juan barely escaped with a handful of soldiers back to Daliang. Thus Zhao was saved from Wei.