President Donald Trump and House Speaker Nancy Pelosi (D–Calif.) are locked in a battle of wills over the border wall. After declaring a "barrier…absolutely critical to border security" during his Oval Office address, Trump walked out of a meeting with Pelosi and Senate Minority Leader Chuck Schumer when they refused to budge on the wall money. This may well be a prelude to Trump acting on his threat to declare a national emergency and using unobligated Pentagon funds to get the military to build a wall.

That would be a terrible abuse of his power, because there is no wall-worthy national security threat at the border.

Contrary to Trump's claims, a wall won't do much to stanch the flow of drugs to this country. Why? As best as can be determined, most of the heroin and cocaine intercepted on its way to the U.S. comes through legal ports of entry. And even if the wall did substantially block smugglers, the same sorts of drugs—or close substitutes—would be instead generated domestically, as long as there is a demand for them.

As for the human beings coming across the southern border, they are increasingly asylum seekers, and their cases deserve to be heard and processed quickly—which means investing in more immigration judges, not misdirecting resources on a misguided wall.

No matter how many times it is pointed out to Trump, he simply won't admit that the flow of illegal immigration is rapidly trending downwards. In 2000, the authorities apprehended 1,643,679 unauthorized migrants. In 2017? 303,916. There was a slight uptick in 2018, but nothing approaching a "crisis"—a word that Trump used six times in his seven-minute national address earlier this week. So going by the sheer numbers, if there was ever a time for a wall, it has already passed.

If the quantity of immigrants doesn't justify a wall, their "quality" doesn't either.

The administration has already taken a walloping for its whopper that 4,000 terrorists were apprehended at the southern border in 2017, a figure that was off by 4,000. Yes, about 3,000 "special interest" people were flagged entering from that side, but that merely means that they hail from countries that are a potential source of terrorism, not that they are terrorists themselves. No one who has come in from the southern border has ever conducted a terrorist attack. Even the ultra-restrictionist Center for Immigration Studies acknowledges that the administration is vastly exaggerating the terrorist threat.

What about other kinds of criminals? Trump has never backed away from his statement that Mexico sends us "rapists" and "criminals" rather than its "best" people. In truth, Mexico no longer sends us very many people at all—unlike back in 2000, when Mexicans made up 98 percent of the total migrants and Central Americans about two percent. As Stephanie Leutert, director of the Mexico Security Initiative at the University of Texas at Austin, points out, the split is now close to 50-50.

And among those coming in, criminals are the rarest of rare exception.

Leutert notes:

Since the Trump administration took office, the Border Patrol has detected fewer gang members crossing irregularly than during the Obama administration. In FY2017, these detections amounted to 0.075 percent of the total number of migrants (228 MS-13 members out of 303,916 total migrants). When combined with MS-13's rival, the Barrio 18 gang, the number rises only slightly to 0.095 percent. This is far from the "infestation" of violent gang members described by the president.

Furthermore, unlike the immigrants coming from Mexico, 98 percent of who were working-age men looking for better economic opportunities, half of the apprehended immigrants from Central America are families, many of them not-so-threatening women and children without men, predominantly from three countries: Honduras, Guatemala, and El Salvador.

Leutert notes that although the migrants from Guatemala tend to come from rural areas to escape extreme poverty (often mortgaging their farms to make the journey), those from Honduras and El Salvador are predominantly urban dwellers trying to get away from gangs. (Those gangs, in turn, formed after America started deporting criminal aliens back in droves.)

The previous unaccompanied minor "crisis" occurred not because Central American parents were acting irresponsibly, as many restrictionists claim. It was because they were trying to extricate their kids from the clutches of gangs trying to recruit them. "Boys of eleven years old (or younger) may be recruited as lookouts and teenage girls may be eyed for becoming members' 'girlfriends,'" Leutert says.

Families are now coming together to seek asylum. One would think that would gain them some brownie points from immigration hardliners who were slamming them for sending kids alone. But no! Now they are being accused of using kids as "pawns" to gain entry into the United States (because, per the Flores ruling, kids can't be kept in detention for longer than a few days so families who come with them are more likely to be "caught and released"). But that's not the case. Families are all fleeing together because gangs have started charging exorbitant extortions that are beyond the means of small mom-and-pop businesses to pay. And the price for failing to pay up, Leutert points out, is often death.

If there were lots of criminals and terrorists trying to sneak across the border undetected, a wall might help. But asylum seekers are actually trying to get caught because they want to live and work legally in the country. Indeed, as Vox's Dara Lind points out, they turn themselves in to the first border agent they encounter—at a port of entry if they can, but if those are too backed up, or if they're forced to languish for days and weeks because the Trump administration will only let a few in at a time (an illegal practice called metering), then between ports.

All a wall would do in that case is seal off access points between ports, creating bigger backups at ports of entry. Far from alleviating the brewing humanitarian situation at the border, as Trump claimed in his address, a wall would exacerbate it.

Restrictionists also claim that asylum-seeking families that are "caught and released" typically just disappear, never to be heard from again. But that's a highly dubious claim, to say the least. In one Obama-era program where asylum seekers were paired with case managers before being let go, the asylum seekers had a 100 percent attendance record at court hearings. They also had a 99 percent rate of check-ins and appointments with Immigration and Customs Enforcement, according to a Department of Homeland Security report.

More generally, the immigration advocacy group American Immigration Council published a report four years ago that looked at studies from over the previous two decades examining how well asylum seekers fulfilled their legal obligations. It found "very high rates of compliance" among those "who were placed into alternatives to detention."

The report cited a 2000 U.S. government-commissioned study that found an "83 percent rate of compliance with court proceedings among asylum seekers who were found to have a credible fear in the expedited removal process." It also showed an 84 percent compliance rate among asylees under minimal supervision, and 78 percent among those who were unsupervised.

This makes sense: The penalty for living in the country without authorization—both legal (given that unauthorized people have a very hard time obtaining visas) and in lost wages—is so high that asylum seekers have a built-in incentive to do things by the book. That's why, far from wasting money on the wall, it would be better to invest in more judges and legal hearings for a speedy dispensation of asylum cases.

The real crisis will be if Trump declares a national emergency to deal with his fake threat.