With the current state of airline travel today, you shouldn't be doing things that make other people nervous.
Agreed.
@Radeng:
Go a bit further:
1. Beware of speaking arabic languages.
2. Don't dress like people from the Middle East.
3. Don't roll out your carpet in front of the boarding desk and start praying.
In the name of safety and security they'll take more and more of our freedom.
If I had seen that boy I probably would have thought: "Hey, that's great. This boy cares about some darkest hours in recent history!"