Homeland Security Presidential Directive-2: Combating Terrorism Through Immigration Policies [open pdf - 29KB]
"The United States has a long and valued tradition of welcoming immigrants and visitors. But the attacks of September 11, 2001, showed that some come to the United States to commit terrorist acts, to raise funds for illegal terrorist activities, or to provide other support for terrorist operations, here and abroad. It is the policy of the United States to work aggressively to prevent aliens who engage in or support terrorist activity from entering the United States and to detain, prosecute, or deport any such aliens who are within the United States."
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