It is hard to hate this game because it has such a simple premise to it that really works. The coolest thing is that you have a lot of control over how the missile goes. Despite the website this comes from, this doesn't seem to be much of an actual defense game. If anything, it's an offense game as you go around attacking other stuff. It could use some more detail in the background but other than that it's good. It just goes to show that you do not need a lot of elaborate stuff to make a good game.
The music is nice and has a really smooth flow to it. It even helps when you are trying to sync the missile to where it's supposed to go. My advice is probably to keep the mouse as close to it in the beginning as possible. You are not able to change direction as I have tried that. It might have helped if you could control the position of the missile launcher.