After caving on the shutdown, President Trump continues to insist that American taxpayers shell out $5.7 billion for a border wall (or is it a fence?) that he promised would be paid for by Mexico. There are many reasons to oppose Trump’s quixotic demand for a wall, but the most straightforward one is also the simplest: It won’t work. Trump’s wall would be a gargantuan boondoggle, an ineffective and expensive barrier that would likely displace rather than deter illegal crossings and cross-border smuggling. And that $5.7 billion Trump is demanding could be put to much better use to actually secure the border.

In the past, Trump has boasted that he has won political support because people realize that he knows “more about this stuff than anybody" when it comes to border security.

I suspect that Mike Vigil would beg to differ. Vigil served as the former head of international operations at the Drug Enforcement Administration. He spent three years as an undercover agent infiltrating drug cartels in Colombia and 13 years doing the same in Mexico. Vigil posed as a drug trafficker and won the confidence of drug lords. He nearly was killed taking down key players in the Guadalajara Cartel, the criminal network that murdered and tortured fellow DEA agent Kiki Camarena, one of Vigil’s friends. And then he oversaw all international narcotics operations for the largest anti-drug agency on the planet.

In short, he understands the world of traffickers on the southern border because he lived in it for decades. Trump often argues that the wall would stop drug trafficking. So I asked Vigil: Does he think that Trump’s wall would, in any way, limit the flow of drugs into the United States? He didn’t hesitate.

“Why would you want to toss billions of dollars on a useless project that would have absolutely zero impact? Zero impact. … It’s not going to stop anything. They’ll tunnel. They’ll punch holes in it and put French doors with stained glass on that wall. They’ll fly over it” (with cheap drones).

President Trump said Jan. 31 if the barrier between San Diego and Tijuana was taken down House Speaker Nancy Pelosi would be "begging for a wall." (Reuters)

In fact, in areas where barriers already exist — or where drug traffickers worry they’ll be detected by existing surveillance measures — the cartels have developed advanced tunnels. Those tunnels sometimes even include sophisticated rail systems. Some are powered by solar energy. Others have complex ventilation and air-filtration systems. They often originate inside private homes on one side of the border and pop up inside a house on the other side, making policing them difficult.

Vigil told me that some drug kingpins, such as the notorious Joaquín “El Chapo” Guzmán Loera, who is on trial in New York, even sent engineers to Europe to study cutting-edge strategies used in German tunneling. He explained that those investments have unfortunately paid off, creating an extensive underground smuggling network that would not be affected by the creation of a wall on the desert soil above.

“If you took a giant knife and you sliced across the 2,000-mile U.S.-Mexico border, it would look like a block of Swiss cheese because it’s riddled with tunnels,” he said.

That doesn’t mean that border security is a Sisyphean task and that we should give up on it. It’s essential for national security and humanitarian justice to ensure that the government can properly patrol the southern border. But the first question lawmakers must ask themselves when disbursing billions of dollars is will this be a cost-effective way to spend this money? With Trump’s wall, the answer is clearly a resounding “no.”

Additional funds for smart border security could help, though. Vigil points to a few possible solutions: drones, ground sensors that are unattended and better camera systems (to name just a few). But with all of them, border security requires more personnel, so agents can actually tackle the problems they detect. The starting base salary for a border agent is $40,511, so $5.7 billion would go a long way. And more money could also be spent on Coast Guard operations. Officials have said their resources are stretched so thin that they can pursue only 20 percent of the leads that are generated by intelligence.

Vigil supports these ideas, but he also thinks the solution needs to focus on the drivers of illegal flows across the border, be it drugs or people, that come from countries such as Honduras, El Salvador and Guatemala. “I would put some of that money to help these countries combat this scourge that is afflicting their nations. Build up the judiciary, train the security forces, and that would go a long way.”

There are smart and stupid ways to approach border security. Trump’s wall is the stupid way. In negotiations with the White House, House Democrats should make that clear and explain why their plan will secure the border more effectively and at lower cost.

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