What were the "Open Door Notes" about?

The "Open Door Notes," written by U.S. Secretary of State John Hay in the late 19th century, were primarily aimed at ensuring that all countries had equal trading rights in China and advocating for the respect of China's territorial integrity and sovereignty. These notes were a response to the increasing sphere of influence that various foreign powers had established in China, which threatened to limit access to the Chinese market for U.S. businesses.

By promoting the idea that all nations should have a fair opportunity to trade with China without any exclusive rights, the Open Door Policy was not just about economic interests; it was also rooted in a belief in the importance of maintaining China's sovereignty against colonization and division by foreign powers. This diplomatic strategy signified a move towards a more collaborative international trading environment and sought to prevent any single nation from monopolizing trade with China.

The other options do not accurately capture the spirit and intent of the Open Door Notes. They were not about urging attacks or promoting aggressive territorial expansion; rather, they focused on maintaining peace and equality in international trade relations.