an icepick through the keyhole

The thing is, I'm interested in so many things, that it's hard to find focus, and I'll have to figure out a research topic if I'm going to submit a PhD. proposal by the end of next semester. Obviously, if there's a professor who's actually in the field I'm doing stuff I can work under it'll be a lot easier. And I am intrigued by the idea of military justice systems. And as you know, legal history, in the sense that it examines the law and its effects on society at any given period, can illuminate all kinds of other things about that society - its norms, its priorities, its social structure, etc. What I'm hoping is that by going into military justice, I can go through it and find out how Asian-Americans were treated in the US military... which was actually one of the topics proposed in my original MA application.

Am I being too optimistic to hope that once I get my degree out of the way then I'll have time to branch out and research all the other stuff I'm interested in while teaching?