Do all Deists believe that God created the universe and then stepped back?
No, but there are many Deists who believe this way and are probably the majority. They believe that God created the universe and set it in motion based on natural laws and then stepped back and observes (like a scientist and his experiment). This has been related to the idea that God created and then abandoned which is nonsense. However, contrary to popular belief, Deism is not defined by its view of God but is defined by where the belief in God originated (reason). There are some Deists that believe that God acts as a subtle guiding force behind the universe and governs by the natural laws, a sustainer if you will. In each view, an awe and reverence for God and his creation exists and plays a pivotal role for all Deists regardless of belief into the nature of God.