How did the 9/11 attacks change world outlooks in the 21st century?
One significant way in which world outlooks changed after the 9/11 attacks was the increase in police and state security measures. Prior to 9/11, transportation around the world was generally relaxed -- not lax as such, but not overly worried about dangerous items in luggage or screening. Today, especially in the U.S., airport security is the most paranoid it has ever been, and other countries are following suit. The rise of new technology -- such as the "nude scanner" for airports -- has resulted in transportation delays, rising prices, and customer backlash against perceived unfair or prejudiced techniques.
All over the world, suspicion and paranoia have increased as a direct result of the 9/11 attacks, and recent events show no signs of this trend slowing.