Rotation is possible. Activate the (rotate indicating) tool and move the resize/move/rotate handles.
2) Select the rotate tool (whose icon is the universal symbol for "rotate" that can't possibly be confused with anything else)
3) Click once to define an origin
4) Click and drag to interactively rotate about that origin.
This is how the Illustrator rotate tool has worked since, literally, Illustrator 1.0.