Yes, whistling! It's a well-known terrorist technique, first brought to public attention in this country in 1951. Terrorists aren't uniformly brave and no one is brave all the time, so they are taught specialized techniques to reinforce their courage.

Whenever a terrorist feels afraid
He holds his head erect
And whistles a happy tune
So no one will suspect
He's afraid

While shivering in his shoes
He strikes a careless pose
And whistles a happy tune
And no one ever knows
He's afraid

The result of this deception
Is very strange to tell
For when a terrorist fools the people
I fear he fools himself as well

They make believe they're brave
And, tragically, the trick has taken them far
They may be as brave
As they make believe they are

They may be as brave
As they make believe they are

They whistle a happy tune
And every single time
The happiness in the tune
Convinces them that they're not afraid

They believe they're brave
And the trick will take them far
They may be as brave
As they make believe they are