By Dianne Feinstein

Originally published in the San Francisco Chronicle.

The United States is now in the third week of a partial government shutdown that stems from a disagreement between the president and Congress over funding for a border wall. This comes at great cost to more than 800,000 federal workers furloughed or working without pay and at great inconvenience to all Americans.

But debate about the president’s border wall obscures two facts: first, by shutting down key government agencies the president is weakening our national security; and second, we simply don’t need a border wall stretching from the Pacific to the Gulf of Mexico.

By keeping a quarter of the government shuttered, President Trump is forcing 55,000 Customs and Border Protection agents and 50,000 Transportation Security Administration screeners to work without pay. Forcing our first line of defense to give up paychecks is a poor way to improve our safety.

So why is the president forcing the issue? He claims that we’re experiencing a border crisis, but he’s wrong. Unauthorized crossings have been at their lowest levels due to investments in border security over the past two decades. In 1994, Customs and Border Protection reported more than 1 million apprehensions. In 2017, that number was just over 300,000.

It’s also a fact that nearly half of all undocumented immigrants come to the United States legally but then overstay their visas. A border wall would do nothing to curb visa overstays, a legitimate issue that should be addressed through biometric entry-and-exit systems.

The president is also ignoring domestic and international laws that protect asylum seekers. Immigrant families are fleeing horrific violence in Central America, but contrary to the president’s claims, many are turning themselves in at ports of entry to request asylum, not trying to cross the border illegally. Over the weekend, the administration shifted its stance and said it would support allowing asylum seekers to make claims in their home countries rather than coming to the U.S. border. If the administration follows through on this, it would be a positive development.

The president also claims that a wall is necessary to curb the flow of drugs into our country, another deceptive argument. Experience demonstrates that as walls go up, criminals go underground. More than 200 illicit cross-border tunnels have been discovered in the United States since 1990. I visited one in San Diego. Dozens of these included sophisticated elements such as rail tracks, lighting and ventilation.

While many of these tunnels are used to transport illegal narcotics into the United States, they’ve also been used for human smuggling. In August 2017, agents discovered and detained 30 migrants in an underground, cross-border tunnel. The tunnel was more than 300 feet long, and ran under the fencing between Tijuana, Mexico, and San Diego. Tunnels have been uncovered that run as long as a half-mile.

Fighting border tunnels requires cooperation on both sides of the border, and the Trump administration has failed to persuade Mexico to do more on this front. For example, Mexico has yet to criminalize the construction of cross-border tunnels and doesn’t permanently close them upon discovery.

By contrast, a bill I authored in 2007 criminalized the construction, financing or use of unauthorized tunnels into the United States, and another in 2012 provided law enforcement and prosecutors with tools to locate tunnels, identify criminals and punish those responsible. As a result of those laws, as of February 2017, 24 defendants had been charged in a dozen cases, according to the U.S. Department of Justice.

The Border Patrol has also struggled mightily with recruitment and retention. To fill just one agent position, the agency reports that it must interview 133 candidates.

Efforts to hire agents to fill vacant positions have fallen short. The Department of Homeland Security’s Inspector General recently found that the consulting firm hired by Customs and Border Patrol was paid $13.6 million in the first 10 months of its $297 million, five-year contract, which resulted in only two additional agents being hired.

This is a stunningly ineffective and inefficient use of government resources.

There’s also an urgent need to ensure that immigration cases are processed in a timely manner and that immigrants in custody are treated humanely.

Immigration courts have a backlog of more than 1 million cases and immigrants often have to wait for years for their case to be heard.

Customs and Border Patrol facilities are also at a breaking point and simply not designed to house families seeking asylum. Customs and Border Patrol Commissioner Kevin McAleenan explained at a Senate Judiciary Committee hearing last month that they were built for adult men, not mothers and children, and the recent deaths of two migrant children make crystal clear that care is inadequate.

Federal dollars would be better spent on improved medical care and conditions for families in custody and additional immigration judges.

Our country faces many challenges related to immigration, but a $20 billion border wall won’t fix any of them. And keeping the Department of Homeland Security shuttered until a wall is funded will only make matters worse.

Congress should act immediately to reopen the government and then sit down and negotiate responsible solutions to these problems. It’s why we were sent to Washington.

Dianne Feinstein is California’s senior senator in the U.S. Senate.