The U.S. Already Engages in “Extreme Vetting”
A new Cato study provides the first estimate of the number of terrorism vetting failures, both before and after the vetting enhancements implemented in response to the September 11, 2001, attacks.
A terrorism vetting failure occurs when a foreigner is granted entry to the United States who had terrorist associations or sympathies and who later committed a terrorism offense including support for terrorist groups abroad.
Only 13 people — 2% of the 531 individuals convicted of terrorism offenses or killed while committing an offense since 9/11 — entered due to a vetting failure in the post-9/11 security system.
There were 52 vetting failures in the 15 years leading up to 9/11, four times as many as in the 15 years since the attacks. From 2002 to 2016, the vetting system failed and permitted the entry of 1 radicalized terrorist for every 29 million visa or status approvals. This rate was 84% lower than during the 15-year period leading up to the 9/11 attacks. Only 1 of the 13 post-9/11 vetting failures resulted in a deadly attack in the United States. Thus, the rate for deadly terrorists was 1 for every 379 million visa or status approvals from 2002 through 2016.
During this same period, the chance of an American being killed in an attack committed by a terrorist who entered as a result of a vetting failure was 1 in 328 million per year. The risk from vetting failures was 99.5% lower during this period than during the 15-year period from 1987 to 2001.
The evidence indicates that the U.S. vetting system is already “extreme” enough to handle the challenge of foreign terrorist infiltration.
