McLane-Ocampo Treaty

The McLane–Ocampo Treaty, formally the Treaty of Transit and Commerce, was an 1859 agreement negotiated between the United States and Mexico, during Mexico's War of the Reform, when the Mexican liberal government of Benito Juárez was fighting against conservatives. The treaty was controversial in both Mexico and the United States. For Mexico, it was seen as a betrayal of the country by ceding rights to the United States, which had defeated Mexico in the Mexican-American War a decade before, but it promised the financially-strapped liberal government the means to wage war against conservatives. The U.S. Senate rejected ratification of the treaty in 1860. Had it been ratified, it would have given major control over Mexican territory seen as a crucial transit point from the Caribbean to the Pacific Ocean.

The treaty was negotiated by the U.S. Ambassador to Mexico, Robert M. McLane and Melchor Ocampo, Mexico's Minister of Foreign Affairs. It was signed in the port of Veracruz in Mexico on December 14, 1859, which would have sold the perpetual right of transit to the Isthmus of Tehuantepec to the U.S. for $4 million, through the Mexican ports of Tehuantepec in the south, to Coatzacoalcos in the Gulf of Mexico. All the transit would be free of any charge or duty, both for military and commercial effects and troops. It even granted the obligation of Mexican troops to assist in the enforcement of the rights permanently granted to the U.S.

Additionally, it granted rights of passage through two strings of Mexican land: one that would run through the state of Sonora from the port of Guaymas on the Gulf of California, to Nogales, on the border with Arizona; and another one from the western port of Mazatlán, in the state of Sinaloa, going through Monterrey all the way through Matamoros, Tamaulipas, south of present-day Brownsville, Texas, on the Gulf of Mexico. Mexico was also compelled to build storage facilities on either side of the Tehuantepec isthmus. All rights of passage would benefit the U.S. on a perpetual basis.

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