Mexico–United States border
The international boundary separating Mexico and United States extends from the Pacific Ocean to the Gulf of Mexico. The border traverses a variety of terrains, ranging from urban areas to deserts. It is the most frequently crossed border in the world, with approximately 350 million documented crossings annually. Illegal crossing of the border to enter the United States has caused the Mexico–United States border crisis. It is one of two international borders that the United States has, the other being the northern Canada–United States border; Mexico has two other borders: with Belize and with Guatemala.
The vast majority of the current border was decided after the Mexican–American War. Most of the border is situated along the Rio Grande River, which marks the boundary between Texas and northeastern Mexico.
Four American Sun Belt states border Mexico: California, Arizona, New Mexico and Texas. One definition of Northern Mexico includes only the six Mexican states that border the U.S.: Baja California, Chihuahua, Coahuila, Nuevo León, Sonora and Tamaulipas. The total length of the continental border is.
From the Gulf of Mexico, it follows the course of the Rio Grande to the border crossing at Ciudad Juárez, Chihuahua, and El Paso, Texas. Westward from El Paso–Juárez, it crosses vast tracts of the Chihuahuan and Sonoran deserts to the Colorado River Delta and San Diego–Tijuana, before reaching the Pacific Ocean.
Geography
The Mexico–United States border extends, in addition to the maritime boundaries of into the Pacific Ocean and into the Gulf of Mexico. It is the tenth-longest border between two countries in the world.The Mexico–U.S. border begins at the Initial Point of Boundary Between U.S. and Mexico, which is set one marine league south of the southernmost point of San Diego Bay. The border then proceeds for in a straight line towards the confluence of the Colorado River and Gila River. The border continues southwards along the Colorado River for, until it reaches a point south of the Gila River confluence. The border then follows a series of lines and parallels totaling. First, it follows a straight line from the Colorado River to the intersection of the 31° 20′ parallel north and the 111th meridian west. It then proceeds eastwards along the 31° 20′ parallel north up to a meridian west of the point where the Rio Grande crosses the 31° 47′ parallel north, It then proceeds northwards along that meridian up to the 31° 47′ parallel north and then eastwards along that parallel until it meets the Rio Grande.
According to the International Boundary and Water Commission, the continental border then follows the middle of the Rio Grande—according to the 1848 Treaty of Guadalupe Hidalgo between the two nations, "along the deepest channel" —a distance of to its mouth at the Gulf of Mexico. The Rio Grande frequently meanders along the Texas–Mexico border. As a result, the U.S. and Mexico have a treaty by which the Rio Grande is maintained as the border, with new cut-offs and islands being transferred to the other nation as necessary. The Boundary Treaty of 1970 between Mexico and the U.S. settled all outstanding boundary disputes and uncertainties related to the Rio Grande border. The U.S. states along the border, from west to east, are California, Arizona, New Mexico, and Texas. The Mexican states along the border are Baja California, Sonora, Chihuahua, Coahuila, Nuevo León, and Tamaulipas. Among the U.S. states, Texas has the longest stretch of the border with Mexico, while California has the shortest. Among the states in Mexico, Chihuahua has the longest border with the U.S., while Nuevo León has the shortest. Along the border are 23 U.S. counties and 39 Mexican municipalities.
History
Before the Mexican–American War
In the mid-16th century, after the discovery of silver, settlers from various countries and backgrounds began to arrive in the area. This period of sparse settlement included colonizers from different backgrounds. The area was part of New Spain. In the early 19th century, the U.S. bought the lands known as the Louisiana Purchase from France and began to expand steadily westward.After the 1803 Louisiana Purchase, the border between the U.S. and New Spain was not clearly defined. The border was established in 1819 Adams–Onís Treaty between the U.S. and Spain, which specified the northern and eastern borders. Mexico gained its independence from Spain, and the border was reaffirmed in the 1828 Treaty of Limits. Mexico attempted to create a buffer zone at the border that would prevent possible invasion from the north. The Mexican government encouraged thousands of its own citizens to settle in the region that is now known as Texas, and even offered inexpensive land to settlers from the U.S. in exchange for populating the area. The influx of people did not provide the defense that Mexico had hoped for and instead Texas declared its independence in 1836, which lasted until 1845 when the U.S. annexed it.
Establishment of the present border
The constant conflicts in the Texas region in the mid-19th century eventually led to the Mexican–American War, which began in 1846 and ended in 1848 with the Treaty of Guadalupe Hidalgo. In the terms of the peace treaty, Mexico lost more than of land, 55% of its territory, including all of what is today California, Arizona, New Mexico, Utah, Nevada and parts of what is Colorado, Wyoming, Kansas, and Oklahoma. In addition, all disputes over Texas and the disputed territory between the Rio Grande and Rio Nueces were abandoned. The exact border was established by surveyors from both countries, who interpreted the treaty as they completed the United States and Mexican Boundary Survey.Five years later, the Gadsden Purchase completed the creation of the current U.S.–Mexico border. The purchase was initially to accommodate a planned railway right-of-way. These purchases left approximately 300,000 people living in the once-disputed lands, many of whom were Mexican nationals. Following the establishment of the current border, several towns sprang up along this boundary, and many of the Mexican citizens were given free land in the northern regions of Mexico in exchange for returning and repopulating the area.
Later history
The Treaty of Guadalupe Hidalgo and another treaty in 1884 were the agreements originally responsible for the settlement of the international border, both of which specified that the middle of the Rio Grande was the border, irrespective of any alterations in the channels or banks. The Rio Grande shifted south between 1852 and 1868, with the most radical shift in the river occurring after a flood in 1864. By 1873, the moving river-center border had cut off approximately of Mexican territory in the El Paso-Juarez area, in effect transferring the land to the U.S. By a treaty negotiated in 1963, Mexico regained most of this land in what became known as the Chamizal dispute and transferred in return to the U.S. Border treaties are jointly administered by the International Boundary and Water Commission, which was established in 1889 to maintain the border, allocate river waters between the two nations, and provide for flood control and water sanitation. Once viewed as a model of international cooperation, in recent decades the IBWC has been heavily criticized as an institutional anachronism, by-passed by modern social, environmental and political issues. In particular, jurisdictional issues regarding water rights in the Rio Grande Valley have continued to cause tension between farmers along the border, according to Mexican political scientist Armand Peschard-Sverdrup.The economic development of the border region on the Mexican side of the border depended largely on its proximity to the U.S., because of its remoteness from commercial centers in Mexico. During the years of Mexican President Porfirio Díaz, between 1876 and 1910, the border communities boomed because of close ties to the U.S. and the Mexican government's support for financial investments from the U.S. Railroads were built that connected the northern Mexican states more to the U.S. than to Mexico, and the population grew tremendously. The mining industry also developed, as did the U.S.'s control of it. By the early 20th century, companies from the U.S. controlled 81% of the mining industry and had invested US$500 million in the Mexican economy overall, 25% of it in the border regions.
The U.S. Immigration Act of 1891 authorized the implementation of inspection stations at ports of entry along the Mexican and Canadian borders. The U.S. Immigration Act of 1917 required the passing of a literacy test and a head tax by Mexicans wanting to enter the U.S. legally; however, during World War I, when labor shortages grew, the provisions were temporarily suspended. The U.S. Immigration Act of 1924 established the U.S. Border Patrol.
The Mexican Revolution, caused at least partially by animosity toward foreign ownership of Mexican properties, began in 1910. The revolution increased the political instability in Mexico but did not significantly slow U.S. investment. It did reduce economic development within Mexico, however, and the border regions reflected this. As the infrastructure of communities on the U.S. side continued to improve, the Mexican side began to fall behind in the construction and maintenance of important transportation networks and systems necessary to municipal development.
Although the Mexican Revolution caused insecurity in Mexico, it also strained U.S.–Mexico relations. With the Mexican Revolution lasting for 10 years, ending in 1920, and World War I simultaneously occurring between 1914 and 1918, the division between the U.S. and Mexico began to polarize the two nations. Constant battles and raids along the border made both authorities nervous about borderland security. The Zimmerman Telegram, a diplomatic cable sent by Germany but intercepted and decrypted by British intelligence, was meant to bait Mexico into war with the U.S. to reconquer what was taken from them during the Mexican-American War. This inspired the U.S. Federal Bureau of Investigation to monitor suspicious activities and potential violence at the border. Within 10 years, frequent provocations caused border towns to transform into battlefields, which intensified transborder restrictions, brought federal soldiers to patrol the border, and caused the construction of fences and barriers between border towns. When the battles concluded, restrictions for crossing the border were relaxed, and most soldiers were sent home; however, the fences remained as a physical reminder of the division between the two nations. As years passed, more fences and higher barriers were established as attention focused on the boundary demarcation between the U.S. and Mexico.
The first international bridge was the Brownsville & Matamoros International Bridge, built in 1910. The first barrier built by the U.S. was between 1909 and 1911 in California; the first barrier built by Mexico was likely in 1918. Barriers were extended in the 1920s and 1940s.
The Banco Convention of 1905 between the U.S. and Mexico allowed, in the event of sudden changes in the course of the Rio Grande, for the border to be altered to follow the new course. The sudden changes often created bancos, especially in the lower Rio Grande Valley. When these bancos are created, the International Boundary and Water Commission investigates if land previously belonging to the U.S. or Mexico is to be considered on the other side of the border. In all cases of these adjustments along the Rio Grande under the 1905 convention, which occurred on 37 different dates from 1910 to 1976, the transferred land was small and uninhabited.
The Rio Grande Rectification Treaty of 1933 straightened and stabilized the river boundary through the highly developed El Paso-Juárez valley. Numerous parcels of land were transferred between the two countries during the construction period, 1935–1938. At the end, each nation had ceded an equal area of land to the other.
The Boundary Treaty of 1970 transferred an area of Mexican territory to the U.S., near Presidio and Hidalgo, Texas, to build flood control channels. In exchange, the U.S. ceded other land to Mexico, including five parcels near Presidio, the Horcón Tract, and Beaver Island near Roma, Texas. On November 24, 2009, the U.S. ceded 6 islands in the Rio Grande to Mexico. At the same time, Mexico ceded 3 islands and 2 bancos to the U.S. This transfer, which had been pending for 20 years, was the first application of Article III of the 1970 Boundary Treaty.