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Other initiatives

Polk's ambassador to the Republic of New Granada, Benjamin Alden Bidlack, negotiated the Mallarino–Bidlack Treaty. Though Washington had initially only sought to remove tariffs on American goods, Bidlack and New Granadan's Foreign Minister negotiated a broad agreement that deepened military and trade ties. A U.S. guarantee of New Granada's sovereignty over the Isthmus of Panama was also included. The treaty was ratified in 1848 and in the long run it facilitated the Panama Canal, built in the early 20th century. It also allowed for the construction of the Panama Railway, which opened in 1855. The railway, built and operated by Americans and protected by the U.S. military, gave a quicker, safer journey to California and Oregon. The agreement was the only alliance Washington made in the 19th century. It established a strong American role in Central America and was a counterweight to British influence there.