The reason why the liver agreement is invalid

 1. Although Article 4 of the Peace Treaty signed by China and Japan in April 1952 stipulated that "all treaties, agreements, and agreements signed before December 9, 1941 will be invalidated as a result of the war," it was wrong for China to use Kando as its territory. 

2. Japan signed a "Gando Agreement" with the Office in 1909 and handed over its sovereignty to the Office based on the fact that the border between Joseon and the Office at the time was "Tomungang River = Dumang River." However, shortly after the signing of the 1909 Gando Convention, which was discovered on the 8th, the Tomungang River and the Dumangang River are clearly revealed as different rivers in the Japanese map "Waterway Exploration near Baekdusan Mountain Jeonggyebi." It is also evidence showing that the Japanese authorities were clearly aware of this at the time. 

3. The Japan-Korea Treaty of 1905 was concluded while the Japanese side mobilized military police to threaten the representatives of the Korean Empire, and it deserves to be an "obsession to the national representative." Japan-Korea Treaty of 1905, where the emperor's ratification has not been issued, cannot be a formal diplomatic agreement, says Lee Tae-jin, a professor at Seoul National University (National History). Even if the logic that Japan maintained its status as a protective country of the Korean Empire is recognized, it cannot avoid pointing out that the Kando Convention has exceeded the "range of protection rights." In Article 1 of Japan-Korea Treaty of 1905, "The Japanese government can supervise Korea's relations and affairs toward foreign countries," as this only means the right to diplomatic bargaining as a proxy and does not include the right to conclude a treaty. 

The Waterway Exploration near the Baekdusan Mountain Political Monument released on April 4 shows that the Japanese side understood that "Gando Island was Joseon's land," contrary to the "Cheong-Ilgando Agreement" that handed over the sovereignty of Gando to China based on the "Tomungang = Tuman River." It is clear on the map that the actual location of the Tomungang River, which was currently removed from China, was not the Tuman River, but a tributary of the Songhwagang River located northwest of the Tuman River and east of the Sado Baekha. October 1909, when the map was drawn up, was only a month after the signing of the Cheong-Il Road Agreement. The map was prepared in detail based on materials that are difficult for civilians to obtain, and the seal "Book of the Governor-General of Korea" is stamped.