A shouting match has erupted inside the White House between two of President Trump’s top advisers. While angry arguments are typical in the world of stressful, high-stakes White House decision-making, this one has true revelatory potential: It opens a window on a big, festering lie at the very core of Trump’s worldview.

That lie is actually two, interrelated lies. The first is that immigration to the United States is fundamentally a malicious, destructive force that Americans should feel taken advantage of or menaced by. The second is that it can be dealt with primarily through “toughness.” Those lies feed each other: If immigration represents a zero-sum threat, in which migrants or their countries of origin are merely driven by a desire to prey on Americans and America, then a “tough” response will overwhelm that predatory motive. Respond “weakly” and you’re a sucker, a victim.

Bloomberg reports that White House Chief of Staff John F. Kelly and national security adviser John Bolton got into a furious argument over immigration. Bolton sided with Trump, who has raged at Homeland Security Secretary Kirstjen Nielsen for failing to stop families trying to cross the border. Kelly defended her.

The New York Times adds this crucial detail: “The two men also differed over how aggressively to push Central American countries to do more to discourage their citizens from seeking refuge in the United States.”

Trump has been in a seething fury over a recent spike in migrant families trying to cross the border, and more specifically over a caravan of Central American migrant families moving north through Mexico. Trump has accused Guatemala, Honduras and El Salvador of waging an “assault” on the United States and absurdly threatened to use the U.S. military to “CLOSE OUR SOUTHERN BORDER!”

We cannot be sure of the particulars of the Bolton-Kelly dust-up. But it appears Bolton agreed with Trump that DHS is to blame for failing to stop the migration, and that more must be done to force those countries to prevent it.

Some Trump advisers are cynically feeding his ugliest instincts

The backdrop for all this is the argument raging inside the White House over the rise in migrating families. Stephen Miller, the Trump kingdom’s Immigration Iago, has been whispering in Trump’s ear that the United States is being taken advantage of — whether by child smugglers or countries herding immigrants northward isn’t clear — to push Trump to reinstate some form of the family separations he canceled amid intense blowback.

Trump has come to believe that those family separations are the only thing that has worked — in other words, that a tough deterrent is the only answer. Except that this is highly questionable. The Post’s Nick Miroff and Josh Dawsey obtained new internal administration numbers on attempted family crossings, as measured by apprehensions:

The latest DHS figures show 107,212 members of “family units” were taken into custody during fiscal 2018, obliterating the previous high of 77,857 set in 2016.

Family crossings were much higher over the past year — during which the separations were implemented — than the year before. What’s more, Vox’s Dara Lind took a close look at the data and found that during the separations, attempted family crossings did not drop. As Lind concluded, there is “no evidence” that “harsh treatment” has a “deterrent effect.”

A core assumption of Trump’s immigration agenda is that making life as horrible as possible for immigrants — either those trying to cross the border or those living undocumented here — will reduce the flow of immigration and the size of that undocumented presence. Immigration and Customs Enforcement agents now target longtime undocumented residents not just to remove them, but also to spread fear and misery so more “self deport.”

This latter policy, too, has been justified with lies. Trump regularly claims that having undocumented immigrants here means more crime, but much research contradicts this. Low-skilled immigration does not have a meaningful impact on Americans’ economic prospects. And do we even know if “self-deportation” is actually on the rise? I’ve seen nothing demonstrating that. Unleashing cruelty may not even be having that desired effect.

As for the question of whether making life more miserable for would-be migrants deters them, the verdict is in — it doesn’t. The explicitly stated goal of threatening the horrifying prospect of getting separated from your child is deterrence. But such migration is incredibly complicated and driven by all kinds of tangled causes. Alicia A. Caldwell’s in-depth reporting illustrates that these mainly include terrible conditions in origin countries, from severe deprivation to political unrest to crime and corruption and violence. This phenomenon is cyclical.

This is why Caldwell, too, concluded that “attempts to increase deterrence … haven’t been effective.” What is actually needed is more comprehensive regional solutions to those underlying causes, as the Obama administration (which, in fairness, also experimented with much tamer deterrence) at least tried to implement. But as Lind points out, this is made harder when Trump lashes out at those countries — which was at the core of the Kelly-Bolton dispute.

We are trapped in the worldview of Trump’s base

As Sabrina Siddiqui demonstrates, Republicans are running dozens of ads across the country that paint undocumented immigrants as violent criminal invaders. Trump tweets regularly that countries to our south are deliberately unleashing them on us. This latter idea is foundational to Trumpism: In his announcement speech, he didn’t merely slime Mexicans as rapists; he also repeatedly said Mexico is sending them, which is why he vowed to get revenge by forcing Mexico to pay for a wall.

Those vows of retribution — and the vow to build that wall — continue today. If migrants are merely predators, and their origin countries are suckering us by unleashing them northward, then you will of course believe that being “tougher” will both cause the immigrant predators to slink away and bully those countries into refraining from taking advantage of us.

These claims, we are told, will energize the Republican base in the midterms. If this is so, then the GOP base is fully in thrall to this terrible misreading of the situation. But, while public opinion on immigration is complicated, and while many Americans surely have legitimate objections to certain aspects of the globalizing order, majorities are now increasingly inclined to see immigration as a positive force, in direct contradiction of this zero-sum worldview.

The problem is that far too much of our policy response to this complex problem is now springing from that very worldview. And we all have to live with that.

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