Terrorism -- September 11 Terrorist Attacks, 2001 2 War on terrorism, 2001- 2 Civil defense -- 1 Government policy -- 1 Intelligence officers -- 1 Islam 1 more ... Islamic fundamentalism -- 1 Law enforcement -- 1 National security -- 1 Prevention -- 1 Prevention. -- 1 Religious aspects -- 1 Undercover operations -- 1 less ...