The big, beautiful wall (fence / barrier / steel slats / electronic entry control / etc.) on the southern border of the United States is working as intended and is, in fact, functioning quite well. How do we know this? Because of these 3 things:

1. The number of people illegally entering the country has been cut in half
2. The vast majority of drug interdictions occur at official points of entry
3. Wages for farm workers are rising, up from minimum wage to as much as $17/hr

"Hey, wait a minute, EdG!!" you're probably thinking. Our hero Democrats in Congress have thwarted Evil Trump's plan to build his big, beautiful wall. So how in the hell can the wall already be working?

Easy peasy. There's already a wall (etc.) in place on a substantial portion of the southern border. How did this happen? Thank earlier Congresses and especially thank the 109th Congress, which passed the Secure Fence Act of 2006.

By May 2011, DHS reported completing 649 miles of fencing (99.5% of the 652 miles planned). The barrier was made up of 299 miles of vehicle barriers and 350 miles of pedestrian fence. The fencing includes a steel fence (varying in height between 18 and 26 feet) that divides the border towns of Nogales, Arizona in the U.S. and Nogales, Sonora in Mexico. A 2016 report by the Government Accountability Office confirmed that the government had completed the fence by 2015.

Source: Secure Fence Act of 2006

Who voted for the Secure Fence Act? In the Senate, Biden (D-DE), Boxer (D-CA), Clinton (D-NY), Dodd (D-CT), Feinstein (D-CA), Obama (D-IL), Schumer (D-NY) and all but a handful of other Senate Democrats voted for it. In the house, all but 6 Democrats voted for it. Nancy Pelosi was one of the 6 Nay votes.

But the barrier built under the Secure Fence Act covers only about 1/3rd of the entire border. The total length of the continental border is 1,954 miles. Trump's wall, which Democrats are now opposed to, would blanket the rest of the border. Meanwhile, construction on portions of the wall continues apace. For example:

U.S. Customs and Border Protection (CBP), in partnership with the U.S. Army Corps of Engineers (USACE), has awarded a contract to construct up to 14 miles of secondary wall and up to 15 miles of primary pedestrian replacement wall in California within the U.S. Border Patrol’s (USBP) San Diego, Yuma, and El Centro Sectors. The contract was awarded on December 20, 2018 to SLSCO Ltd. using CBP’s Fiscal Year (FY) 2018 appropriations.

Source: Border Wall Contract Awards in California

As noted earlier, the existing barrier is doing its job. But the job is incomplete because the wall is incomplete. Here's a fuller explanation of where the wall is successful.

Success #1: Reduced Illegal Border Crossings

There is little doubt that the border thingamajiggy has drastically reduced illegal immigration. A common method of estimating illegal entries to the United States uses a derivative of Border Patrol actual apprehensions. The theory is that when more people try to cross, more are caught by Border Patrol. As the chart shows, the number of apprehensions decreased because of the secure fence. As they say, good fences make good neighbors.

Success #2: Increased Drug Interdictions

Another way to tell that the border doohickey works is through drug smuggling interdictions. It's well-known that the majority of illegal drugs entering the US come through ports of entry. This is demonstrated by the fact that most drug busts occur at official entry points and not at wide open sections of border. In other words, there are few if any people with "calves the size of cantaloupes" trudging through the desert carrying sacks of illicit drugs.

Instead of human mules, most drug busts at the border occur at official entry and checkpoints. This proves the barrier is functioning correctly. After all, a fundamental purpose of the wall is to funnel those seeking entry toward one or more locations controlled by US Customs agents.

According to U.S. Customs and Border Protection statistics, 90 percent of heroin seized along the border, 88 percent of cocaine, 87 percent of methamphetamine, and 80 percent of fentanyl in the first 11 months of the 2018 fiscal year was caught trying to be smuggled in at legal crossing points.

[A side note: There's often confusion about who does what at the border. Customs agents man ports of entry and screen people openly entering the country. Border Patrol agents work the border and border checkpoints looking for those entering the country illegally. Both play a role in catching smugglers.]

Success #3: Improved Farm Wages

The third component proving wall success is that fact that a) wages for farm workers are rising and b) employers of illegal workers are griping.

Everyone knows or should know that farm worker jobs comprise a fairly small segment of overall jobs in the United States and that only a fraction of illegal workers hold jobs in agriculture. According to the US Bureau of Labor Statistics, there were 856,300 agricultural workers as of July, 2016. Reference: BLS - Agricultural Workers. Estimates of the number of those jobs filled by illegal workers range from 25% to 50%, or about 215,000 to 430,000 workers.

It's also known that illegal farm workers are paid 15% less than US workers and often lack the benefits and protections afforded legal workers. Despite that discrepancy, wages for farm workers are rising (see Farmworker wages up 3% in 2017; average now $12.51) and at least some of that is attributable to decreased illegal immigration due to the border fence slats.

Meanwhile, farm owners are complaining that they have to pay workers market wages and compete against other employers. Another owner complaint is that enforcement of labor laws causes loss of laborers willing to work for less money.

The president of the Nisei Farmers League, Manuel Cunha, has grown quite frustrated. He said other industries — construction, restaurants, manufacturing — are trying to lure the same pool of workers, which puts upward pressure on wages. More troublesome, he said, is the federal push for stricter enforcement of immigration laws.

He said when federal authorities contact Central Valley farm contractors and ask them to produce documentation of their workers' right to work in the country, between a third and half of the employees flee.

"Ninety-nine percent of the time the workers never come back. It's a disaster," he said. "I will tell you, I have never seen bigger destruction for employers."

Source: Farm wages rise as labor supply tightens

Opportunity: Decreased Migrant Deaths

At least 412 people lost their lives attempting to cross the border to the US in 2017. Some of the victims drowned trying to cross the Rio Grande or in flooding caused by heavy rains near the river. Others died of exposure and dehydration trying to cross the desert. A few died from violent causes, and the cause of death for many was indeterminable.

Reference: US-Mexico border migrant deaths rose in 2017 even as crossings fell, UN says

Why are these deaths happening? Because the existing barrier works but is incomplete. As we know, the fencing and other components installed thus far effectively restrict access to the stretches of the United States they cover. But the closed sections tend to push would-be border jumpers toward more dangerous desert and river crossings, thereby increasing migrant deaths. Completing the fence is the best way to solve this problem.