Getting caught and imprisoned, possibly executed, represents danger.
Getting killed by someone trying to stop you represents danger.
Flying a plane which you are aboard into a building represents danger.
Confronting these dangers with the confidence - however misguided - that you are not acting in vain represents - according to the dictionary - courage.

No, terrorist leaders are not blowing themselves up. They might be, indeed, cowards.

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I want to know everything
I want to be everywhere
I want to fuck everyone in the world
I want to do something that matters