It is one of American history's greatest ironies that, since 2016, amidst the space age, with a generation of nuclear deterrence, instant global communications, and social media, that a border issue has dominated public attention. In an age of globalization, it is fashionable to dismiss geopolitics as "tribal," reminiscent of old Europe when armies crossed borders to start wars. The new phenomenon, "cyber" war, would come from computers and attack other communication targets.
Meanwhile, tens of thousands of unwelcomed (mostly) illegal "aliens" south of the border threaten to subvert the culture and change the existential nature of the country. Some refer to this as an "invasion," no-less-so than Lee's invasion of Pennsylvania.
Is this a sudden event, or an "emergency" as the President has called it? Or, more to the point, is it just another historical repetition like war and peace, nation/country and sovereignty/territory? Are the millennials right, that we can escape (or erase) the past?
First, the border itself is one of the most contentious places on earth. The total length, from the Pacific Ocean to the Gulf of Mexico, is almost 2,000 miles (1,954). It is the most human-transited site in the world, with approximately 350 million documented crossings annually. The area is characterized by diverse terrain, deserts, rugged hills, daily sunshine, and two main rivers - Rio Grande and Colorado. There are 48 designated crossings, in California, Arizona, New Mexico, and Texas, and 330 ports of entry. The largest port of entry, San Ysidro, transits about 50,000 vehicles and 25,000 pedestrians every day. Total population on both sides is 12 million.
The history pre-dates the Republic itself.
As early as the mid-16th century, with the discovery of silver, settlers from all over began to arrive, and, until the early 19th century, the area remained a kind of undefined "no-man's land." This changed with the Louisiana Purchase (1803) and Mexican independence from Spain (1821), when both independent Texas (1836-45) and Mexico vied for control of the region. Constant warfare without a defined border led to Texas statehood (1845), the Mexican War (1847-48), and the Treaty of Guadalupe-Hidalgo (1848), wherein Mexico ceded over half of its territory to the U.S. (nearly a million square miles). This treaty saw the states of California, Arizona, New Mexico, Utah, Nevada, and parts of Colorado, Wyoming, Kansas, and Oklahoma eventually join the Union.
Abraham Lincoln served only one term in Congress (1847-49) but left a fairly-unknown and curious border legacy during his term. President James K. Polk declared war due to Mexico's invasion north of the Rio Grande, an area that had been left disputed by both sides. Opposing the war, Lincoln repeatedly demanded from the floor of the House that Polk indicate the precise American "spot" that Mexico had occupied. Colleagues soon called Abe "spotty Lincoln" for his efforts in vain. Ironically, Lincoln began his public political career as a committed war resister.
A subsequent treaty (1884) officially declared the middle of the Rio Grande as the border, and an International Boundary and Water Commission (IBWC) was established in 1889. Further Immigration Acts (1891, 1917) provided supervisory procedures for legal immigrants, including literacy tests and a head tax. The 1924 Act established the U.S. Border Patrol (USBP).
The Mexican Revolution (1910-20) caused serious friction between the two countries, including a series of military raids into Arizona and New Mexico by rebel chieftain Pancho Villa and armed clashes between the American and Mexican armies. Woodrow Wilson sent the Army into Mexico both in 1914 and 1916, the latter led by General Pershing. Neither incursion produced any tangible result, and Pershing was brought home in January 1917. At the same time, Foreign Minister Arthur Zimmerman of Germany sent a dispatch to the Mexican government promising the return of lands taken in 1848 if Mexico would join the Kaiser in World War I. Mexico declined, but Wilson used this note as a causus belli to declare war on Germany, a decision that ultimately made the U.S. a superpower.
Thus, the Mexican border provoked perhaps the most decisive moment in U.S. foreign policy history.
During this time period, various fences and barriers were built as border towns were progressively turned into battlegrounds. Today, there are an estimated 654 miles of these impromptu barriers.
After World War I, the U.S. government encouraged legal immigration from Mexico as it was simultaneously issuing quotas against immigration from the rest of the world (1924 Immigration Act). Southwestern farmers were eager for cheap Mexican labor, while the Mexican government actually opposed this flow as their own crops were left rotting in the fields. Throughout the 1920s, an annual rate of 62,000 legal workers and 100,000 illegals crossed the border annually, with American farmers actually welcoming the illegals.
During World War II, the "Bracero" program, encouraged by Mexico, regulated the border, with over 5,000 Mexican soldiers helping supervise the region. By 1964, approximately 2 million Mexican laborers had crossed, with a peak of 445,000 in 1956.
By then, however, the Eisenhower Administration grew nervous on the border issue and promptly (1954) began "Operation Wetback," a program to round up and deport illegals. Using 700 military vehicles plus cars, buses, and airplanes, and doubling border agents (to 1700), approximately 1.7 million illegal aliens were deported, all with the cooperation of Mexican authorities, who loaded them up and transferred them deeper into the interior.
"Wetback," appropriately, ends this background (the name alone would be called "racist"). The nostalgic past ends here, and "current" history likewise begins. If nothing else, this brief glance back shows that the border issues we have now are hardly unique and that, through turmoil, chaos, congestion, and outright war, both countries have seemed to survive.