why did US involvement in Manchurian?

U.S. involvement in Manchuria during the early 20th century was primarily driven by strategic and economic interests. Following Japan's invasion of Manchuria in 1931, the U.S. sought to protect its investment and trade interests in the region while promoting the Open Door Policy, which aimed to ensure equal trading rights in China. Additionally, the U.S. was concerned about Japanese expansionism and its implications for regional stability and American security interests in the Pacific. This involvement set the stage for a broader engagement in Asia during World War II.