What do you mean by "eight thousand miles of clouds and the moon"?

"Eight Thousand Miles of Clouds and Moon" means to take troops to the battlefield and travel eight thousand miles to the north, only to see the clouds and moon in the sky.

This word comes from Yue Fei's "Man Jiang Hong Chong Guan", and the original text is as follows:

Angry, leaning against the railing, resting in the drizzle. Looking up, screaming in the sky, strong and fierce. Thirty fame, dust and earth, eight thousand miles of clouds and the moon. Don't be idle, white and sad!

Jingkang is ashamed, but it is still snowing. When do courtiers hate their guts! Driving a long car, breaking through the lack of Helan Mountain. Eat pork when you are hungry, and drink Hun blood when you are thirsty. Stay from the beginning, clean up the old mountains and rivers, and go to the sky.

Yue Fei (1103-11year) was born in Tangyin, Xiangzhou (now Henan). In the autumn of three years (1 129), Wu Shu invaded the south, and Du Chong, who was left behind by Jiankang (now Nanjing, Jiangsu), surrendered without a fight. Jin Jun was able to escape the natural barrier of the Yangtze River and quickly captured Lin 'an, Yuezhou (now Shaoxing), Mingzhou and other places, and Gaozong was forced to exile at sea. Yue Fei led a lone army to fight behind enemy lines. First attack Guangde Jin Jun defenders, and win six out of six. When Jin Jun attacked Changzhou, he led the troops to help each other, winning four out of four. The following year, Yue Fei set an ambush in Niutou Mountain, the martial arts of Jin Wu were broken, Jiankang was recovered, and 8 Jin Jun was forced to withdraw northward. Since then, Yue Fei's reputation has spread all over the country, and the sound has shocked the country. In July, Yue Fei was promoted to the governor of Tongzhou Town and Taizhou, with more than 10,000 troops, and established a disciplined and brave anti-gold force-Yue Jiajun.

In the third year of Shaoxing, Yue Fei was awarded the banner of "loyal minister Yue Fei" by Emperor Gaozong for destroying Li Cheng and Zhang Yong. In April of the following year, Yue Fei sent his troops to the north, crushed the puppet troops of the rulers and recovered six counties, including Xiangyang and Xinyang. Yue Fei was also promoted to the Qingyuan Army for his merits. In December of the same year, Yue Fei defeated the nomads from Luzhou (now Hefei, Anhui) and the nomads were forced to return to the north. In the fifth year of Shaoxing (1 135), Yue Fei led the army to suppress Yang Yao's rebel army and recruited 50,000 to 60,000 elite soldiers, which greatly increased the strength of Yue Jiajun.

In the sixth year of Shaoxing, Yue Fei made another northern expedition and captured Yiyang, Luoyang, Shangzhou, and then besieged Chen and Cai areas. However, Yue Fei soon found himself alone, without reinforcements and food, so he had to withdraw to Ezhou (now Wuchang, Hubei). During the Northern Expedition, Yue Fei's ambition was unfulfilled, and when he was guarding Ezhou (now Wuchang), he wrote the word "Manjianghong", which was a swan song throughout the ages.