In the Chu-Han dispute, Liu Bangxian killed Xiang Yu, and just signed a peace treaty, taking the gap as a non-aggression boundary. At this time, Liu Bang's counselor advised Liu Bangxian to fight Xiang Yu. Xiang Yu thought that the treaty had just been signed, and Liu Bangxian would not fight at this time, so there was no defense at all. As a result, he was attacked by Liu Bangxian, surrounded by Han Xin's flying daggers, and ended up committing suicide in Wujiang River. In the history of the world, Caesar was assassinated in ancient Rome, and Octavian and Anthony fought for Roman rule. Anthony was superior to Octavian, but he didn't listen to the advice of his subordinates, dared not go back to Rome, and didn't make any serious preparations. As a result, Octavian took control of Rome first, and Anthony was defeated as soon as he arrived at the army. There is one more thing you must know. In the Sino-Japanese War of 1894-1895, Japan took the lead in attacking Korea and the Yellow Sea, and was passive everywhere after the Qing Dynasty. Although there are many and complicated reasons for the defeat of the Qing Dynasty in the Sino-Japanese War, Japan's preemptive strike is a very important reason.