Yang Di led a million-strong army to personally conquer Koguryo, a small country. Why did he come home in a fiasco?

Emperor Yang Di personally conquered Koguryo, a small country, with a million troops, but he was defeated because of his arrogance. At that time, he had actually captured a city, but he did not pursue it. Instead, I fought with Koguryo intermittently. A few months later, Sui Jun was exhausted, and then Goguryeo stepped in and quickly turned the tide.

Koguryo is not an honest country. It occupies most of Liaodong Peninsula and Korean Peninsula, so whenever something happens, it goes to the Central Plains to make trouble. Of course, Hu Hanjun in the Northern and Southern Dynasties was also in trouble, and it was common to play Koguryo frequently. After the unification of Sui Dynasty and Northern Zhou Dynasty, Koguryo left a lot of Liaodong land in the chaos. After Yang Guang pacified the world, he met Goguryeo's emissary in Turkey. When his life came, Goguryeo promised to visit the emperor, but he couldn't change it when he went home.

Therefore, at the beginning of the war against Koguryo, it should be said that Sui Jun's fighting capacity was still quite strong. Although thousands of troops have been mobilized, Koguryo has been defeated by the first army. Goguryeo chose to surrender when she could not be defeated. At this time, she followed the army and did not reach the battlefield. Therefore, the vanguard troops did not dare to accept surrender privately, so they could only wait for Yang's arrival in such a stalemate. But Goguryeo secretly rested at this time and strengthened her consolidation.

The Sui Dynasty lost its vitality in this war, and lost a lot of troops and materials, which made the economy of the Sui Dynasty gradually decline and its strength gradually declined, which was also the reason why Sui Jun could not be pacified after the uprising.