Elected officials only change their policies when enough people make enough noise. And not until then.
Public policy isn't made in the capitals of the world -- it never is. It's made in the streets.
The Iraq war will only end when enough people make it their priority to bring American troops home, and not until then. The Bush Administration and the Congress will not budge until they are forced to.
When hundreds of thousands of people start marching in the streets to bring our troops home, they will come home.