How do you explain terrorism to kids

It's all over the news, Osama's capture.
I can't shield her anymore, but how do I even start to explain Terrorism to Rachel at the tender age of five?

I started planning it in my head with empty phrases like

sometimes people don't agree

and

bad things happen

but let's face it, she'd have seen right through those in an instant and followed up with why, why, why?

I thought maybe I should explain more about war and liken terrorism to war in some way. But that still falls short. War is between two nations or tribes, based on power and money and domination. The terrorism we know today is not that; it is about fear and sacrifice and vengeance and many other things which I do not understand.

But now I know.
Now I have no doubt.
Now I will treat her with the intelligence and understanding I know she has.

I will start at the beginning with the conflict between USSR and Afghanistan. Paint the picture, show her the scene of war and power and dominion.

I will explain how the west promised to save Afghanistan but instead left the country with a power vaccuum ready to be filled by a succession of power hungry leaders.

I will help her understand how a once great country suffered; and how the richer west could have done more to help but didn't. And help her see that in this place it must have been easy to grow weary and angry and full of vengeance towards those who could have brought change.

Then I will remind her of the museum we visited in NYC, about the buildings that were destroyed by planes, about the lives that were lost. I will reassure her that this will not happen again. And I will hold her as I explain that that is an act of terrorism.

It's hard, I wish I didn't have to explain it, but I can avoid it no longer. I pray that she will be able to understand even some small extent and that this will help her wish for peace throughout her life.

Wish me luck