Terrorists outside the country will continue to try to circumvent existing measures that prevent them from entering the United States.
Even if immigration procedures are improved, they will do little to protect the US homeland from attacks by American citizens.
Other methods to protect against the threat of domestic terrorism will remain a necessary part of counterterrorism efforts in the United States.
The recent attacks in Paris and San Bernardino prompted significant debate about whether to reform US immigration law to help protect the country from terrorism. Though US Republican presidential candidate Donald Trump’s remarks about banning Muslims from traveling to the United States have garnered the most attention, several other immigration-related initiatives are being pursued.
On Dec. 8, the US House of Representatives passed a measure to limit access to the United States for people who traveled to Iraq or Syria after March 1, 2011 (the civil war in Syria began on March 15). The bill also contained a provision requiring countries participating in the United States’ visa waiver program to share counterterrorism information and issue biometric passports or be expelled from the program. Meanwhile, the State Department said it is investigating the visa issuance process that allowed San Bernardino shooter Tashfeen Malik to enter the US in 2014 as the fiancée of the American-born Syed Farook.
The idea behind these measures is rooted in the fact that most of the attackers involved in the Nov. 13 Paris attacks were European citizens who had traveled to Syria. However, most jihadists who enter Syria and Iraq do so illegally; consequently, there are no official records of their passage, or entry and exit cachets stamped in their passports. In the past, when jihadists did receive stamps in their passports while entering or exiting places like Pakistan or Afghanistan, they often reported their passports stolen to hide evidence of their travel. This is where the provision requiring countries to share counterterrorism information comes in. Most evidence of foreign citizens traveling to Syria and Iraq comes via intelligence, not immigration records.
However, using immigration policy as a counterterrorism tool is not a new idea. The United States initiated a wide-ranging review of visa issuance policies and procedures after the 9/11 attacks and instituted many changes. A review of immigration procedures also occurred in the wake of the failed 2009 underwear bombing. For the most part, these changes have been effective. Thanks to improvements in the visa issuance process — specifically the array of linked databases that are queried during processing — terrorist groups such as al Qaeda and the Islamic State have struggled to get trained professional terrorist cadres into the United States to conduct attacks. Their frustration has led them to adopt the leaderless resistance model of terrorism and call on Muslims living in the United States and elsewhere in the West to conduct attacks.
Indeed, a review of attacks and plots directed against the United States since 9/11 reveals that the international terrorist threat to the United States has stemmed predominately from US citizens rather than from foreigners traveling to the country from abroad. (This is not counting domestic terrorists who are all US citizens and who, as noted by people such as Peter Bergen and Dr. John Horgan, have actually killed more people inside the United States since 9/11 than international terrorists.)
Various plots instigated after 9/11 have included citizens of visa waiver countries. Shoe bomber Richard Reid and the British citizens involved in the 2006 liquid bomb plot are examples. Also, al Qaeda in the Arabian Peninsula attempted to bypass US immigration screening by using a non-Yemeni, Nigerian citizen Umar Farouk Abdulmutallab, for the underwear bomb plot.
However, more US citizens have been involved in failed or busted plots than foreigners. Examples include the so-called “dirty bomber” Jose Padilla; would-be New York subway bomber Najibullah Zazi; failed Times Square bomber Faisal Shahzad and University of North Carolina SUV attacker, Mohammed Reza Taheri-azar. Then there are the likes of Terry Lowen; Adel Daoud and Daniel Boyd and his sons, to name a few.
Regarding fatal attacks in the United States since 9/11, American citizens have been involved in all of them except the 2002 El Al ticket counter attack in Los Angeles, which was conducted by Hesham Mohamed Hadayet, an Egyptian citizen who had been granted political asylum. The American citizens involved in deadly attacks inside the United States include D.C. sniper John Mohammed, Little Rock recruitment center shooter Abdulhakim Mujahid Muhammad (Carlos Bledsoe), Fort Hood shooter Nidal Hasan, Boston Marathon bomber Dzhokar Tsarnaev (his brother and co-conspirator Tamerlan was pending naturalization), Queens hatchet attacker Zale Thompson, Chattanooga shooter Muhammad Abdulazeez and San Bernardino shooter Syed Farook (although his wife and co-conspirator was not a citizen and had entered the United States on a fiancee visa).
All this is not to say that immigration policy and procedures should not be reviewed and improved as much as possible. Terrorists will continue to try to get around the measures that are keeping them from traveling to the United States, and every effort should be made to keep them out.
It is also clear, though, that U.S. citizens pose a very real international terrorist threat to the US homeland, and no changes in immigration policy will prevent attacks by citizens. Americans should not permit changes in immigration policy to give them a false sense of security. The use of other counterterrorism tools aimed at countering the threat from citizens — including domestic terrorist suspects — must continue.
LEAD ANALYST: SCOTT STEWART