How Will You Use Your Wish?

I was going to ask this yesterday, but I found I had a hard time answering it myself, and I figured I ought to be able to answer my own question. I still can't come up with a decent response. Can you?:

You have just been tapped on the head by the Calvo fairy's magic wand and granted one wish. The wish can be used to make one specific change in policy, institutions, etc., anything at all, and your goal is to make the largest possible improvement in the economic system in the US with a single, narrowly focused change. It is up to you to decide what "improvement" means. What change do you want to make?