By James Varney, RealClearInvestigations
October 31, 2023

Hundreds of people on the FBI’s terrorist watchlist have almost certainly slipped into the United States amid millions of other illegal immigrants during the last three years, according to former federal officials and experts.

“You have to be extremely naïve to not be significantly concerned about this,” said Rodney Scott, former chief of U.S. Border Patrol from 2020 to 2021. “Regardless of what the Biden administration may claim, what it said during the campaign and the executive orders taken in January 2021 have been interpreted around the world as the border is open. You’re insane if you don’t think terrorists will use that to their advantage.”

In the aftermath of Hamas’ terrorist attack against Israel on Oct. 7, President Biden, without mentioning the border, told “60 Minutes” that the threat the U.S. could face from terrorists in the country had escalated.

Although the terrorist threat linked to the border crisis is impossible to quantify, some experts find the available numbers alarming. During Biden’s first three years, a record-shattering 6.5 million-plus immigrants have been “encountered” by border authorities. That pace is increasing: The most recent monthly figures, September’s, showed another record number of monthly encounters – 269,735.

At the same time, federal officials have seen an alarming increase in border crossers listed on the U.S. Terror Screening Dataset, the official name for what is commonly called the “terrorist watchlist.”

In fiscal 2023, which ends this month, Border Patrol agents have apprehended 172 such people, all but three of them along the southwest border. When all U.S. places of entry are added – by land, sea and air  – another 564 people on the watchlist were caught, bringing the total to 736.

By way of comparison, between fiscal 2017 and 2019, Border Patrol agents apprehended a total of 11 people on the terrorist watchlist. Scott sounded an alarm to Congress in the 2021 period when the total jumped to 16. “When a number doubles it gets your attention, and we’ve moved way beyond that,” he says now.

Yet the “known unknowns,” to use Defense Secretary Donald Rumsfeld’s famous phrase, indicate the problem is even worse, according to experts. For one, the “terrorist watchlist” is only as good as the information that has been entered into it.

“Not everybody’s on the watchlist,” said Todd Bensman, who has tracked Central American immigration routes and the southern border for years with the Center for Immigration Studies and is the author of “Overrun: How Joe Biden Unleashed the Greatest Border Crisis in U.S. History.”

“There have been thousands and thousands – tens of thousands – of people from the Middle East who have entered and it’s completely reasonable, even the president has acknowledged it, to worry that some of those could be, or could become, terrorist threats,” Bensman said.

Scott, who spent a half decade in counterterrorism at the Department of Homeland Security before moving to Customs and Border Patrol, said that as legal immigration channels dried up, criminals and terrorists began to seek people who would not appear on any intelligence agency’s datasheet.

“They’re looking for what they call ‘clean skins,’” Scott told RealClearInvestigations. “People with no type of record who can operate freely. They are continuously looking for new channels they can exploit, and they’ve shifted their ports of entry and increased those coming with no prior record.”

Mark Morgan, a former chief operating officer and commissioner with Customs and Border Patrol, echoed that point, telling RCI that “the fact someone isn’t on that list could just mean they haven’t dipped their toe in the pond yet.”

Using a hypothetical, Morgan said border authorities might ask a 30-year-old man from Lebanon if he has any association with Hezbollah, and in some rare cases do a check with the country of origin.

“What’s he going to say? And not every other country has precise, up-to-date information or maybe a good relationship with the United States,” he said. “We can’t even verify the ones we encounter.”

But experts warn that the number of “encounters” is only the known part of the equation. Far more frightening, they say, are the unknown numbers who have snuck into the country.

Through the use of surveillance videos from blimps, drones, and satellites, along with old-fashioned gumshoe work of studying footprints, CBP produces a figure it calls “known gotaways.” That stands at 1.7 million during the Biden administration. Morgan said he considers the “absolute floor” for the real figure is the public number plus 20%.

That would put the total over 2 million. Those unknown hundreds of thousands are uniquely disquieting, in part because so many took measures to dodge border patrol agents. Most current border crossers know that under the Biden administration’s policies, if they surrender at the border they can apply for amnesty or some other favored status and will simply be processed and released to await a distant court date. Thus, most people trekking into the U.S. from Mexico now give themselves up, or simply sit down on U.S. soil and await Border Patrol, according to current and former agents.

“And they’ve lost track of people that already came in,” Scott noted.

Scott and others said it stands to reason that people on the terror watchlist would be far less likely to give themselves up. Instead of becoming an encounter, many are probably “gotaways.”

It’s not clear if DHS or CBP has issued new directives or policies since Biden said he planned to meet with them after Hamas’ Oct. 7 attacks. The agencies declined to comment on specific policies. Joshua Trevino, with the conservative Texas Public Policy Foundation, told RCI there does not appear to have been any change in operations on the ground in Texas.

“Nothing has been made public, which is probably because they haven’t done anything,” he said.

CBP does not breakdown the nationalities of those it encounters, although immigrants from 180 of the world’s 195 recognized nations have been encountered at U.S. borders in the past three years, according to Morgan. Scott said San Diego officers told him they have dealt with 200 languages this year.

A San Diego 'Situational Awareness' Bulletin

In one sign of the growing concern, the Daily Caller reported on Oct. 25 that an internal bulletin from CBP’s San Diego office warned that “foreign fighters of Israel-Hamas conflict may potentially be encountered at southwest border.”

Specifically, the “situational awareness” bulletin cautioned about those with ties to Hamas, Hezbollah, and Palestinian Islamic Jihad, all groups designated as terrorists by the U.S. government.

CBP did not dispute the accuracy of the report but declined to comment on internal documents. A spokesperson told RealClearInvestigations that to date “CBP has seen no indication of Hamas-directed foreign fighters seeking to make entry to the United States.”

The potential threats are two-fold: fighters sponsored or directed by terrorist groups, like those cited in the San Diego bulletin, or people who may have some sympathies with radical Islamic groups and are prompted to act by the war.

To some extent, the former has already occurred, Bensman said, pointing to a federal case concluded in April. Former Al Qaeda fighter Shihab Ahmed Shihab pled guilty in Ohio to plotting to assassinate former president George W. Bush. Shihab flew into the U.S. in 2020, and told undercover FBI agents that after overstaying his visa he had smuggled two Hezbollah operatives across the southern border, half of the team he planned to use.

The team would arrive in the U.S. via international travel to Brazil and then by foot through the Darien Gap, which joins the continents at Colombia and Panama. A federal official familiar with immigration patterns told RCI that “increased migration from South America is a major factor in these increased encounters,” but stressed that is true for all crossers and that those who appear on the U.S. Terror Screening Dataset are “uncommon.”

Bensman, citing other cases of dubious crossings, said that is scant solace to concerned Americans.

“So, we know of one plot,” he said.

It is what authorities call “HVEs,” or “homegrown violent extremists” that constitute the biggest threat, according to some. On Sept. 26, less than two weeks before Hamas attacked, the Council on Foreign Relations argued that “homegrown threats still loom larger than the southern border.”

It was far more likely that terrorists acting in the United States would be motivated by “white supremacist” thinking, or inspired by lone-wolf jihadist terrorists, like the killer at the Pulse nightclub in Orlando. The CFR did not respond to questions from RCI about the situation after Oct. 7.

GOP Sen. Ted Cruz’s home border state of Texas is ground zero in the massive influx of illegal immigration the U.S. has seen since Biden’s inauguration.

“This administration is making America less safe and is making the world less safe,” Cruz said. “As the [San Diego] memo rightly notes, terrorists crossing the southern border will try to obscure their background. Because if they are coming here, there’s a very real possibility they are coming here to commit acts of terror.”

Cruz, who went to the border last week with four other Senators, said on his podcast Monday that border agents told him of a new Biden policy in the past year amounting to "guidelines for non-pursuit." Under it, he said, agents pursuing migrants are barred from any actions "that could potentially endanger someone's safety," such as transporting apprehended migrants in a vehicle with not enough seatbelts for all.

Texas Republican Gov. Greg Abbott’s office did not respond to multiple queries about the situation on the border since Hamas’ attack, and the Lone Star State’s Department of Public Safety declined to comment.

The combination of a huge increase in the number of immigrants apprehended via the U.S. Terror Screening Dataset, the 1.7 million or more “gotaways,” and the easier ability terrorists have to enter the U.S. now via cartel-controlled pathways should serve as a warning to policymakers, many immigration and anti-terrorism experts believe.

“It’s beyond a real concern now,” Mark Morgan said. “What happened in Israel should tell you two things: that global terrorism is alive and well and that there can still be massive intelligence failure. So, if you asked the intelligence community right now how many of the 1.7 million plus gotaways might be a terrorist threat the honest answer is ‘we don’t know.’ If you ask if there could be a sleeper cell the honest answer would have to be ‘we don’t know.’”