It has now been four days since The Washington Post reported that President Trump has considered sending those who cross the Southern border to sanctuary cities. And despite the White House’s initial effort to downplay the idea, it seems this is a conversation Trump would very much like to have. After contradicting his own officials and confirming the idea was under consideration, Trump tweeted about it repeatedly over the weekend — even challenging sanctuary cities to make good on their pro-immigrant ideals.

As a political strategy, raising the idea makes some sense for Trump. As an actual policy, it makes next to none.

Trump’s rhetoric about undocumented immigrants and asylum seekers has not just been about how they are taking advantage of lax American laws or that they are in the country illegally but that they are also dangerous. He has decried them as gang members, “animals” and even terrorists. He has said Mexico and Central American countries are sending their dregs northward. “They’re bringing drugs, they’re bringing crime, they’re rapists,” Trump said in his 2015 presidential announcement speech, “and some, I assume, are good people.”

So what better way to deal with the increasing problem at the Southern border, Trump reasons, than to ... tell these alleged criminals they’ll get a one-way ticket to a community that will welcome them?

The first major issue with this is that, regardless of where these people are sent, they can go wherever they want after that. The Post’s Nick Miroff and Tim Meko this weekend showed us where people tend to go once they cross the border, and it’s to nearly every corner of the country. If people have the means and wherewithal to get from the border to Crookston, Minn., what’s to stop them from, after they get sent to San Francisco, simply resuming their plans to go wherever they initially intended to go?

Supporters of this policy would argue that they might just stay in the sanctuary city because it is welcoming, but there are reasons people make long treks to places like Crookston rather than heading straight for sanctuary cities. They may have family in the area. They may know there is work waiting for them. And being diverted initially upon entry isn’t likely to deter many of them from reaching wherever it is they hope their final destination will be.

The second issue is that this does nothing to address the allegedly huge problems Trump brought up. There is no evidence that these immigrants or asylum seekers are responsible for more crime than American citizens, and Trump’s own administration has said there is no evidence of terrorist groups accessing the United States via the Southern border. But even if Trump were right, what would turning such people loose in the American homeland do? If they stay in the sanctuary cities, those cities would have to deal with them, yes. But so might the federal government. And if they have plans to join gangs like MS-13 or hatch terrorists plots, giving them a free pass into American society — any part of it — would seem like a really bad idea.

Even if they did stay in sanctuary cities, that would also run counter to Trump’s stated warnings about this group. Sanctuary cities are less likely to turn undocumented immigrants over to federal authorities for minor offenses -- or even to ask about their legal status. Having them reside in these cities would seem to allow the ne’er-do-wells among them to stay off the radar of a federal government who might hold them accountable and prevent such the kind of tragedy Trump warns about.

And finally, there is the incentive that this would create. Trump has rather clearly embraced things like family separation as a deterrent — in hopes that it would send a message to other would-be border-crossers that they would rather not deal with all that crossing the border entails. This policy would create the opposite incentive. It would tell people who cross the border illegally or seek asylum that they would get a one-way ticket to what are mostly major American cities. That seems a much more attractive prospect than simply being detained.

All of which is to say this likely isn’t actually a serious policy consideration by Trump. He likes to stir the pot. He wants to put sanctuary cities and those who support them in the position of saying, “No, we can’t take these people,” and have these people look like hypocrites to Trump’s base. I’m not sure it’s had the desired effect, apart from the odd reaction from people like Cher.

But more than anything, the supposed policy idea is a complete non sequitur when it comes to Trump’s stated reasons for a border crackdown. It’s intended to be punitive and perhaps elicit some kind of action by Democrats, but it probably wouldn’t even really satisfy those goals.