Why are we still in war? Better yet, Why are we still over seas?

Well, as it is obvious Saddam hussein is dead and now we're supposed to live happily ever after right? but the drama continues. The cost of war sense 2001 to now is over $1,000,000,000,000 dollars. Now, I believe this money could had gone to better use rather than having to make it mandatory to cut funds for war support. With this kind of money spent, the value of an American dollar just means nothing more but hard labor for war support.