Of the 859,629 refugees admitted from 2001 onwards, only three have been convicted of planning terrorist attacks on targets outside of the United States, and none was successfully carried out. That is one terrorism-planning conviction for every 286,543 refugees that have been admitted. To put that in perspective, about 1 in every 22,541 Americans committed murder in 2014. The terrorist threat from Syrian refugees in the United States is hyperbolically over-exaggerated and we have very little to fear from them because the refugee vetting system is so thorough.

The brutal terrorist attack in France last Friday reignited a debate over accepting refugees from Syria and the Middle East. A Syrian who applied for asylum could have been one of the attackers, although his passport was a forgery. (As of this writing, all identified attackers have been French or Belgian nationals.) Governors and presidential candidates have voiced opposition to accepting any Syrian refugees, while several bills in Congress could effectively end the program.

There are many differences between Europe’s vetting of asylum seekers from Syria and how the United States screens refugees. The geographic distance between the United States and Syria allows our government to better vet those seeking to come here, while large numbers of Syrians who try to go to Europe are less carefully vetted. A lax security situation there does not imply a lax security situation here....

Refugees are processed from a great distance away and are more thoroughly vetted than asylum seekers as a result. In the United States, a refugee is somebody who is identified by the United Nations High Commissioner for Refugees (UNHCR) in a refugee camp. UNHCR does the first round of security checks on the refugee according to international treaties to which the United States is a party and refers some of those who pass the initial checks to the U.S. Refugee Admissions Program (USRAP). The referrals are then interviewed by a U.S. Citizenship and Immigration Services (USCIS) officer abroad. The refugee must be outside the United States, be of special humanitarian concern to the government, demonstrate persecution or fear of persecution due to race, religion, nationality, political opinion, or membership in a particular social group, and must not be firmly resettled in another country.