How was the Forbidden City destroyed?

Li Zicheng occupied Beijing in the late Ming Dynasty and was defeated by Dourgen. When he retreated in a hurry, he set fire to ouchi. As a result, Jiumen and the former imperial court in Beijing were severely damaged, so that the emperor shunzhi had to be enthroned at Taihemen when he entered the customs. In the period of the Republic of China, someone proposed to tear down the three pavilions and turn them into western-style city halls, which was stopped by the telegram of the warlord Wu at that time (although Wu was a warlord, it was indeed a great achievement). When Beijing was occupied by the Japanese, the national treasure of the Forbidden City moved to the south, and the building was not damaged much. Japanese officials must get a permit to visit the Forbidden City. In the Battle of Pingjin, in order to protect the ancient capital Beijing from the destruction of artillery fire, * * * defeated the Fu Uprising, thus saving the Forbidden City from disaster. Recently, at the beginning of the Cultural Revolution, Premier Zhou sent guards to surround the Forbidden City. Someone tried to tear it down and failed. Therefore, it is fortunate that the Forbidden City survived all kinds of disasters and was finally preserved.