Becoming an RN in the military?

I recently graduated with a BS in nursing and I will soon have 1 year of labor and delivery nursing experience as well as newborn nursery and level one special care nursery experience. I have always wanted to travel and I think military l&d nursing would be a great experience. I have no idea where/how to get started though. I don't know which branch would be best for what I want to do. I've heard good things about the marines and the air force though. Also, I've heard that because I have a bachelor's degree that I would automatically become an officer, is that true and what benefits/responsibilities go along with being an officer? Does anyone have any military RN experience to share or how I should go about getting more information abut this?