Emperor Wu of the Han Dynasty began to fight the Xiongnu soon after he came to power, and he fought against the Xiongnu until his later years, after more than forty years. Moreover, his generals have also changed several times, from Wei Qing, Huo Fuyi, and Li Guang in the early period, to Li Guangli and Li Ling in the later period, it is already two generations, and Emperor Wu of Han is still fighting with the Xiongnu.
If the Xiongnu have always been a threat to the Han Dynasty, it is also reasonable for Emperor Wudi of the Han Dynasty to fight against the Xiongnu. But in fact, since Wei Qing and Huo Fuyi attacked the Xiongnu many times, they no longer posed any threat to the Han Dynasty, in this case, why did Emperor Wu of Han continue to fight against the Xiongnu?
The policy of peace and pro-harmony is actually a policy of inequality and humiliation, but for the Han Dynasty, its strength is not as good as that of the Xiongnu, and coupled with the newly established regime, the country is unstable, and it can only adopt new policies to prevent the outside world from within.
Liu Bang adopted a policy of peace and affinity towards the Xiongnu, which is estimated to be the same meaning, first dealing with the Xiongnu, waiting until the Han Dynasty became stronger and stronger than the Xiongnu, and then solving the Xiongnu problem once and for all.
This is the historical and psychological background in which Emperor Wudi of the Han Dynasty wanted to firmly and constantly fight against the Xiongnu. The Han Dynasty was bullied by the Xiongnu for seventy years, the Han Dynasty endured for seventy years, and then silently accumulated strength, and in the generation of Emperor Wu of the Han Dynasty, the state finally accumulated enough strength to crush the Xiongnu in one fell swoop and eliminate the threat to the northern border. With the strength of a generation, the merits of the world are obtained, so even if Emperor Wudi of Han does not fight the Xiongnu, the descendants of Emperor Wudi of Han will attack the Xiongnu.
Huo Wentai was known as the Young General, his youth was crazy, and his flesh and blood fang gang made the Xiongnu feel frightened, and it was also Huo's disease that hit the Xiongnu the hardest. Li Guang was not as stable as Wei Qing, nor as dangerous as Huo's illness, and he was the least hit on the Xiongnu among the three, and he was never appreciated by Emperor Wu of Han, but he was the highest rated in later generations, leaving behind the famous sentence of "The king does not see the hardships of the battlefield, and still remembers General Li".
Although Emperor Wudi of Han went all out to develop the military, he did not slack off politically, reused Dong Zhongshu, and adopted the ideological policy of "deposing hundreds of families and respecting Confucianism alone." In general, Emperor Wudi of Han was a relatively wise emperor and created the prosperous era of Han Wu.