Okay. This act was passed when there was the attack on the World Trade Center by those who wanted to attack our safety using the airplane. We need to be able to arrest those people even though we cannot lay charges. If we have reason to believe they will conduct a terrorist attack, then we need to be able to prevent them from travelling. That's why we need to add the high-risk traveller to our no-fly list.
On March 10th, 2015. See this statement in context.