Historians have always said that the war to conquer Koguryo was a naked aggression by feudal nobles in Sui and Tang Dynasties against small and weak countries, an expedition with no sympathy for people's resources and materials, and an aggression by feudal military imperialism. What's more, this is an unnecessary conquest.
So is this really the case? Let's take a look at how much the Sui and Tang Dynasties paid for Koguryo.
In 598 AD, King Koguryo led tens of thousands of cavalry to harass western Liaoning, and Emperor Wendi of Sui sent 300,000 troops to attack. As a result, in bad weather, food and grass could not be supplied, and plague prevailed in the army. Nine times out of ten, the deceased was killed. In 6 12 A.D., Emperor Yang Di sent an army of1133,800 people, claiming to be 2 million, and personally took the lead in attacking Koguryo, which ended in fiasco.
In this way, millions of lives were buried in the east of Liaohe River. After Koguryo won, he built tens of thousands of bodies of Sui soldiers into a "sit-and-watch" to demonstrate to Emperor Yang Di.
In 6 13, Yang Di personally incorporated Koguryo for the second time, which failed. In 6 14, I personally recruited Koguryo again, which also failed.
Yang Di's crazy conquest of Koguryo brought serious consequences to the country. Due to extensive conscription and huge expenses, the construction of canals and other projects seriously delayed farming, causing a large number of young men to die, so that there was a terrible situation of "insufficient men and insufficient women", and all localities rose up one after another. It can be said that the demise of the Sui Dynasty was actually an indirect death in the battle for Koguryo.
The following Tang dynasty, after accepting the lessons of the demise of the Sui Dynasty, acted cautiously everywhere, which made the world appear a rare scene of pacification. But only in the case of collecting Goguryeo, the wise Emperor Taizong of SHEN WOO, like the tyrant Yang Di, vowed not to stop until Goguryeo was destroyed.
In 645 AD, Emperor Taizong led six armies to set out from Luoyang and personally levy Koguryo. Despite the staged victory, due to the desperate resistance of the defenders and the approach of late autumn, the soldiers could not stay long, and were forced to move troops back to the DPRK, and tens of thousands of soldiers died in battle. However, Emperor Taizong did not give up because of this failure. Later, he repeatedly ordered the border to harass Koguryo.
In his later years, Emperor Taizong ordered Sichuan and other places to cut down trees and build ships in order to collect Koguryo. As a result, the villagers rioted, and the court used tens of thousands of troops to suppress it. The clever Emperor Taizong of SHEN WOO almost followed the old path of Yang Di.
After Tang Gaozong Li Zhi succeeded to the throne, the final elimination of Koguryo was put on the agenda. Although he is not as brilliant as his father, he met the best opportunity in history.
In 666 AD, Koguryo was in civil strife, and Emperor Gaozong took this opportunity to take Li Ji as the general manager of Liaodong March, command the whole army and fight Koguryo separately. Two years later, Tang Jun joined forces and advanced to Yalumen. The defenders of Koguryo city either fled or surrendered. On September 12th, the same year, Tang Jun arrived at the gates of Pyongyang. Koguryo monk Prudential opened the gate and Tang Jun rushed into the city. At this point, Koguryo died.
After reading this, let's review it. What is the fundamental reason why the Sui and Tang emperors tirelessly conquered Goguryeo? Is it really the high-sounding reasons of "going against the sky" and "being impolite" mentioned in most history books? Or is it what most historians thought at first? None of them are right! In fact, a word from Emperor Taizong has already clarified the truth.
In 645 AD, before going out to war, Emperor Taizong once said to the left and right, "Today is a big decision, but Liaodong is not a guest. My successor is strong because of the scholar Ma Sheng, and my adviser led a conquest. I took it for myself and left no future trouble." Spare no effort to destroy Goguryeo is the foundation of Sui and Tang Dynasties.
Koguryo in the 6th and 7th centuries has actually developed into a powerful regional kingdom in East Asia, posing the most direct and dangerous threat to the rejuvenation of China. At that time, it was like Carthage to Rome in the third century BC, Manchu to Ming in the seventeenth century, and Britain to China in the nineteenth century.
Therefore, if the Sui and Tang Dynasties want to prosper, Goguryeo must be eliminated.