A nifty analysis by Reuters that helps explain the broader decline in illegal border crossings since Trump took office.

Just one question: What happens when would-be illegals realize that Trump is bluffing?

In December, 16,000 parents and children were apprehended; in March, a month in which immigration typically increases because of temperate weather, the number was just over 1,100…

Trump has spoken about the need to crack down broadly on all illegal immigrants. But, internally, according to the DHS officials familiar with the department’s strategy, his administration has focused on one immigrant group more than others: women with children, the fastest growing demographic of illegal immigrants. This planning has not been previously reported.

In the months since Trump’s inauguration, DHS has rolled out a range of policies aimed at discouraging women from attempting to cross the border, including tougher initial hurdles for asylum claims and the threat of prosecuting parents [as human traffickers] if they hire smugglers to get their families across the border…

For months, Central Americans had heard about Trump’s get-tough policies. And public service announcements on radio and television presented bleak pictures of what awaited those who traveled north. Some of the ads were funded by the United States, others by United Nations agencies and regional governments.

The linchpin of the PR strategy was having U.S. officials float the idea publicly of separating mothers from their children after they’re caught here and detained. I wrote about that last month. Thanks to an Obama-era ruling by (ta da) the Ninth Circuit, by law the feds have to quickly release children brought to the U.S. illegally — although they don’t have to quickly release their parents. That means the entire family can’t be held together, which creates a dilemma. You either release the whole bunch, which is bad immigration policy, or you separate the kids from their mothers and hand them over to HHS custody, which is fraught politics. Team Trump realized early that the best way to solve that dilemma is to try to prevent it from happening by convincing would-be illegals with kids not to make the trip in the first place, or else. One radio ad running in Honduras, quoted by Reuters, has a woman saying of her child, “It’s been a year and I don’t know if she is alive or dead. I’d do anything to have her here with me. Curse the day I sent her north.” Tough stuff.

So far, though, the “or else” part has been mostly a bluff. DHS backed off the idea of separating kids from their mothers a few weeks ago, and Reuters notes that no parents have been charged as human traffickers as yet. Still — a 93 percent decline. I wondered recently if Nixon’s “madman theory” of foreign policy, which is being emulated in some ways thus far by Trump, also applies to immigration policy. If would-be illegals know the president is hostile and might impose draconian penalties on them for crossing the border, even if he hasn’t yet, how much deterrent effect does that have? Maybe more than we think:

But the symbolism of Trump in the Oval Office and the threat of extended detention has already deterred many migrants. Migrants are scared, explained Jose, a young Honduran man staying at the San Bosco shelter in hopes of getting to the U.S. They might be less scared in the future, he said, but for now they’re waiting…

“Is it true I’ll go to prison for two years if I get arrested?” a Honduran man named Mynor asked in Spanish.

He said he’d been deported from the U.S. four times already, and that he hadn’t been convicted of any crimes. But he’d spent several months in jails in Nevada, Texas, and Arizona before those deportations, he added, and he didn’t want to go back.

The perception of a broad crackdown is worth something in deterrence even absent an actual crackdown, which may or may not happen down the road. Given that the Kushnerites are in ascendance in the White House and the Bannonites are in disfavor, no one would be surprised if Trump’s ramped-up immigration enforcement policy eventually boiled down to building the wall and calling it a day. Two wrinkles, though. One: The sense that the White House is hostile to border crossings is also affecting legal border crossings. One research firm estimates that tourism from Mexico to the U.S. will drop by seven percent this year, producing a loss of $1.1 billion, and is likely to drop further next year, generating another $1.6 billion in losses. Two: As noted up top, unless Trump really does order a crackdown, eventually aspiring illegals will catch on that he’s more bark than bite and border crossings will begin to rise again. In particular, what happens if Trump continues down the path he seems to be on with DREAMers and ends up making a deal to legalize them? If fear of the “madman” is de-incentivizing illegal immigration, realizing that he’s sympathetic to some illegals — especially younger ones — is apt to drain some of the fear among mothers across the border that they’ll be separated from their kids if they enter the U.S. Deterrence via PR is a smart early strategy for the administration as it gets its bearings, but it has a shelf life.