On July 29, 1904, Japan’s Count Katsura met with Secretary of War (later President) William Howard Taft to resolve the grievances between the two countries. Japan agreed to accept the US presence in Hawaii and the Philippines and in exchange we agreed to give Japan a free hand in Korea.
First, in speaking of some pro-Russians in America who would have the public believe that the victory of Japan would be a certain prelude to her aggression in the direction of the Philippine Islands, Secretary Taft observed that Japan’s only interest in the Philippines would be, in his opinion, to have those islands governed by a strong and friendly nation like the United States...Count Katsura confirmed in the strongest terms the correctness of his views on the point and positively stated that Japan does not harbor any aggressive designs whatever on the Philippines...
Second, Count Katsura observed that the maintenance of general peace in the extreme East forms the fundamental principle of Japan’s international policy. Such being the case,...the best and in fact the only means for accomplishing the above object would be to form good understanding between the governments of Japan, the United States and Great Britain...
Third, in regard to the Korean Question, Count Katsura observed that Korea being the direct cause of our war with Russia, it is a matter of absolute importance to Japan that a complete solution of the peninsula question should be made as a logical consequence of the war. If left to herself after the war, Korea will certainly draw back to her habit of improvidently entering into any agreements or treaties with other powers, thus resuscitating the same international complications as existed before the war. In view of the foregoing circumstances, Japan feels absolutely constrained to take some definite step with a view to precluding the possibility of Korea falling into her former condition and of placing us again under the necessity of entering upon another foreign war. Secretary Taft fully admitted the justness of the Count’s observations and remarked to the effect that, in his personal opinion, the establishment by Japanese troops of a suzerainty over Korea to the extent of requiring Korea to enter into no foreign treaties without the consent of Japan was a logical result of the present war and would directly contribute to permanent peace in the East. His judgment was that President Roosevelt would concur in his views in this regard, although he had no authority to give assurance of this..."
The Taft Katsura agreement signaled US acceptance of Japanese control of Korea which had been achieved in February 1904 when Japanese forces invaded Korea. Although the Korean Emperor agreed under duress to the Japanese demands, he sent Mr. Homer Hulbert, an American and long time resident of Korea to Washington to protest and seek aid under the 1883 American-Korean Treaty. He was not allowed to present his protest to President Roosevelt. He was advised he had no credentials from the existing government of Korea, i.e. the government imposed by Japan.
We had failed to honor our 1883 treaty with Korea when we gave our OK to the Japanese protectorate, then used the existence of a new government under the protectorate as an excuse for that failure. Japan occupied and oppressed Korea until she was defeated in WW two.
Why did we do this? The US cited turbulent conditions in Korea prior to the Japanese take over. But I have to wonder whether we were afraid Japan would attack our forces in the Philippines and Hawaii if we opposed them regarding Korea. After all, the Japanese navy had just defeated Russia in two brilliant naval battles. What was the relative naval strength of he US and Japanese navy? This requires more study.