The Sino-Japanese War was an all-round contest between China and Japan, from the supreme commander to the emperor to ordinary soldiers, and the gap between the two countries was everywhere. So many gaps accumulated together, triggering a qualitative change, and the Manchu Qing defeated so quickly, so thoroughly, to everyone's surprise. Let's start at the level of the Supreme Commander.
The story of lying down and tasting guts is familiar to everyone. After Yue Wang Gou Jian was defeated by the State of Wu, he endured humiliation and burden for ten years, and finally made a comeback and destroyed the State of Wu. This allusion teaches us to be patient, a gentleman to take revenge, and ten years is not too late. Unexpectedly, the modern history of East Asia staged a real scene of lying down and tasting guts, and this time the actor was the Emperor of Japan.

What many people may not know is that the Beiyang Fleet also had a highlight moment, the naval guns were ready to fire at Japanese cities, and Li Hongzhang directly threatened the Japanese consul, saying that the Beiyang warships could go to war against Japan at any time. Japan actually obediently obeyed and lost money to the Manchus. This was the Nagasaki Incident that occurred in 1886.
At that time, the four Beiyang capital ships led by Zhenyuan and Dingyuan were carrying out maintenance in Nagasaki, Japan, and when the Beiyang sailors went ashore, they had serious conflicts with the Japanese ronin and the police, and each had casualties. Li Hongzhang only then uttered these words to the Japanese side.
As a result of the incident, the Japanese side compensated 52,500 yen to the Qing government. This is not a small amount, until World War II, the monthly salary of Japanese generals was only 550 yen, and the monthly salary of the lowest soldiers was 3 yen, and 52,500 yen could be considered a huge amount. The Japanese Navy had just started at that time, far inferior to beiyang, and had to endure this breath. The gunboat diplomacy of the Beiyang Fleet was a success.
Since then, Japan has aimed to catch up with and surpass beiyang and desperately built a navy. The following year, the Emperor took the lead in donating 300,000 yen to the Navy. Under the emperor's leadership, the whole country donated more than 1 million yen a year. More than 30 percent of Japan's annual fiscal revenue is invested in military expansion.
From the Nagasaki Incident in 1886 to the signing of the Maguan Treaty in 1895, it was exactly ten years, and it was perfectly realized. Japan went from being a small country to the only great power in Asia, and the Manchu Qing dynasty sank and almost fell into ruin.
In contrast, in the Manchu Qing Dynasty, the rulers' understanding of Japan was very insufficient, and most of them stayed in the Nagasaki Incident, or earlier. He felt that Japan's provocation of China was self-defeating and would inevitably repeat the mistakes of the Tang Dynasty and the Ming Dynasty. Guangxu and Cixi shared the same view.
The superficial scenery of the Western Affairs Movement made the Manchu Qing feel good about themselves, and the Nagasaki Incident made the imperial court believe that the Beiyang Fleet was enough to suppress Japan and ensure the safety of Gyeonggi. Therefore, no one was willing to seriously prepare for the war, and since the Beiyang Fleet became an army in 1888, no ship or gun was added.
At the end of the war, the Guangxu Emperor was actually a staunch warrior faction, and in addition to his contempt for Japan, another important reason was that he wanted to use the victory in the war to regain more power from Cixi.
Although Cixi was a power-loving old woman, she did let him pro-government after Guangxu became an adult, returned some of her power to him, and retained the right to appoint and dismiss officials above the second grade. Guangxu was not satisfied with this, and wanted to create a feat comparable to that of the saints of the past, and return all the remaining imperial power. So, he needs victory in this war.
However, the problem is that Guangxu does not have the quality to command this great war, neither seriously prepares for war, nor does he understand modern knowledge such as war, science and technology, and economy, and because he is longer than the inner palace, he lacks the mature temperament to overcome setbacks and bear the burden of humiliation. During the entire war, he would only order the front-line generals to fight desperately, and as for the tactics of the war and the response to the bad situation, there was no way.
In the first half of the war, it was wishful thinking that a quick victory would be achieved by boosting morale and forcing generals to die. After the collapse of the war in the second half, confidence was completely lost, and he gave up command, and could not listen to the proposal to prolong the war and drag down Japan. I only want to urge Li Hongzhang to end the war and leave a super mess.
Cixi would not have a good response to the war, but at least she would have preferred Li Hongzhang's advice. One of the main reasons why Guangxu refused to listen to Li Hongzhang was that he felt that he was a post-party, and coupled with Weng Tonggong's provocation, Li Hongzhang was unable to play his due role.
Compared with Guangxu and Cixi, Li Hongzhang is considered to know himself and the other. He was well aware that the strength of the Japanese Navy had surpassed that of the Beiyang Fleet, as well as the foreign affairs movement of foreign powers and middle cadres, and the Qing Empire that leaked wind everywhere. Therefore, Li Hongzhang was initially opposed to war, and after fighting a bad war, he put forward suggestions for a long-term war in view of Japan's weakness of insufficient national strength.
However, this kind of self-knowledge can only be regarded as fifty steps and one hundred steps of laughter. Li Hongzhang knew that the Beiyang Fleet and the Huai Army had become corrupt and degenerate, but they should have more than enough self-preservation, and they could still wait for change by relying on their national strength. He also did not expect that the actual battle would be so unbearable, especially the army, which had almost no strength in a war.
From the comparison of the supreme commanders of China and Japan, it can be seen that the Manchu Qing was only more careless than the Wu state of that year, and the internal constraints were more severe. The Japanese side, on the other hand, has the determination to take revenge and the sense and means of war in an all-round way. Before the war began, the end was already predetermined.
[References: Draft History of the Qing Dynasty, Complete History of the Sino-Japanese Sino-Japanese War]