Final answer:
American foreign policy was impacted by spheres of influence in China, as it undermined efforts to establish equal access to China's markets and restricted American intervention and influence. Supporters of the Open Door policy may have regretted their decision due to the advantages enjoyed by European powers within their spheres of influence.
Step-by-step explanation:
American foreign policy was impacted by spheres of influence in China, particularly during the late 19th and early 20th centuries. European powers, such as Britain, France, and Germany, established spheres of influence in various parts of China, which allowed them to control specific regions for economic and political purposes. This undermined American efforts to establish equal access to China's markets, as the European powers sought to maintain their dominance.
The concept of spheres of influence restricted America's ability to intervene in China's affairs and protect its interests. The United States believed in an Open Door policy, which proposed that all nations should have equal access to China's markets. However, the presence of spheres of influence prevented the full implementation of this policy and limited American influence in China.
As a result, American merchants who supported the Open Door policy may have regretted their decision because the spheres of influence created an uneven playing field, favoring European powers. They likely faced difficulties in accessing certain regions or competing with European companies that enjoyed preferential treatment within their respective spheres.
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