Satellite Shootdown

Something cool that I just saw that has to do with technology is that the US is going to try and shoot down a spy satellite. I thought this is really cool, just because I always wondered what they did with that equipment once it was broken beyond repair or no longer needed. I always heard that NASA just left the out dated ones in space, but no one ever told me what they do if they start to fall to earth. Now I know that what they do is shoot them out of the sky. I only hope they have good aim and dont miss. I wonder if they do miss will they have enough time to re-aim and fire again or would the satellite impact the ground, and what kind of damage would it create if it did crash. I am sure though that the government is a good shot and will not miss.