VISA VETTING9/11’s Visa Vetting Failures Were Fixed
Fortunately, the visa vetting system which failed to stop the 19 hijackers from receiving temporary nonimmigrant visas to travel to the United States has been improved, and vetting failures have become far less frequent after the attacks. Unfortunately, the most lasting immigration legacy of 9/11 is how it derailed bipartisan efforts to improve the legal immigration system for peaceful, productive immigrants, students, and travelers.
The worst terrorist attack in world history occurred on September 11, 2001. Many security failures contributed to permitting the attacks to occur, including the inability of the legal immigration system to stop the 19 hijackers from receiving temporary nonimmigrant visas to travel to the United States. Fortunately, the system has improved, and vetting failures have become far less frequent after the attacks.
In 2018, the Cato Institute published my original research documenting terrorism visa-vetting failures from 1987 to 2016. The report demonstrated for the first time that visa vetting failures became much less common in the years following 9/11—despite the US government’s even more aggressive foreign policy and far more legal immigration and travel than before 9/11.
As defined in the report, a visa vetting failure occurs when someone goes on to commit a terrorism offense after entering the United States with views supporting terrorism, regardless of whether they were manifested in any public way. I used this broad definition because, theoretically, the visa vetting process could uncover even privately held views.
Of the 531 individuals killed while committing a terrorist attack or convicted of a terrorism offense—including sending money to groups abroad—from 2002 to 2016, 13 (2.45 percent) were in the United States as a result of post‑9/11 visa vetting failures. This compares to 52 pre‑9/11 vetting failures. The vetting system permitted the entry of one radicalized terrorist for every 29 million visa or status approvals—a rate 84 percent below the pre‑9/11 rate.
This means that improved visa vetting would have had no effect on 97.5 percent of terrorism offenders since 9/11 because they entered before the 9/11 improvements, were born in the United States, or were immigrants who were not vetting failures, according to government sources. Most of these immigrants entered as children or otherwise radicalized after entry, while others were extradited here or deliberately lured here as part of sting operations. Of the 13 post‑9/11 vetting failures, only one (Tashfeen Malik in San Bernardino) killed anyone, compared to the 27 deadly failures before 9/11, meaning that deadly visa vetting failures were reduced by 96 percent.
