Numerous foreign-born individuals have been convicted or implicated in terrorism-related crimes since September 11, 2001, including foreign nationals who entered the United States after receiving visitor, student, or employment visas, or who entered through the United States refugee resettlement program.

Deteriorating conditions in certain countries due to war, strife, disaster, and civil unrest increase the likelihood that terrorists will use any means possible to enter the United States. 

The United States must be vigilant during the visa-issuance process to ensure that those approved for admission do not intend to harm Americans and that they have no ties to terrorism.