How did Polk acquire James Oregon Territory and why?

President James K. Polk acquired the Oregon Territory through a combination of diplomacy and the threat of military action. Initially, the U.S. and Britain shared the territory under the Oregon Treaty of 1818, but tensions grew over the boundary, with Polk advocating for the slogan "54°40' or Fight!" to assert U.S. claims to the northern latitude. Ultimately, in 1846, the Oregon Treaty was negotiated, peacefully establishing the boundary at the 49th parallel, thereby securing the territory for the United States to avoid conflict with Britain. This acquisition aligned with Polk's broader goal of Manifest Destiny, which sought to expand U.S. territory across North America.