Why do terrorists keep terrorizing? Because it works.
The 9/11 attack was utterly successful. It horrified the world to such a degree that they were ready to attack innocent parties to sate their lust of vengeance. This caused many to shift their ideals, to become more revolutionary, and so more suicide bombers were recruited. The ideal revolutionary act is to create a world in which violent revolution thrives.
If we want peace, we need to create peaceful solutions to terrorists acts, because violence only breeds violence.
This is, in the end, spiritual warfare.
Satan is a liar and a murderer. The evil spirits tell lies to humans so that they would fear the innocent and kill them. As many as participate in the system of violence and judgment are judged by that same system. Thus does Satan kill all humanity. By our own hands.
Muslims are not the enemy. Nor are immigrants or refugees.
The enemy is the violence we force down the throat of other nations.
It is not enough for us to stop bringing violence against the good guys. All violence must stop.
It is not enough to give human rights to those who deserve it. We must give human rights to everyone, without exception.
It is not enough to give peace to the peaceful. We must give peace to everyone to teach them how to live in peace.