Final answer:
The U.S. was concerned about China being carved up by foreign powers because it wanted to ensure access to Chinese markets and maintain its strategic position in Asia. The Open Door Policy proposed by Secretary of State John Hay aimed to prevent the creation of exclusive spheres of influence by other powers and promote U.S. commercial interests.
Step-by-step explanation:
Understanding the U.S. Concern Over China's Subdivision
The United States expressed significant concern over the potential carving up of China by foreign powers during the late 19th and early 20th centuries. This was primarily because the U.S. desired to maintain access to the lucrative Chinese markets, which would be threatened by the establishment of exclusive spheres of influence by other imperial powers such as Russia, Japan, and the European countries. This led to the proposal of the Open Door Policy by U.S. Secretary of State John Hay, which sought to protect commercial interests of all nations in China and uphold China's territorial integrity without giving preferential treatment to any one nation.
In addition to economic reasons, the U.S. effort was also rooted in ensuring their own strategic position in Asia was maintained, especially following their acquisition of the Philippines, which served as a strategic gateway to China. The U.S. also aimed to promote their industry and goods in the vast Chinese market, which was highly coveted by American businessmen. To this end, the American Asiatic Association was created to facilitate trade.
The relevance of the Open Door Policy declined after China's transition to Communism in 1949, and the U.S. subsequently ceased recognizing the Communist government, trading instead with Nationalist Taiwan. This marked a significant change in U.S.-China relations, setting the stage for the complex political dynamics that continue to influence international relations to this day.