Force to be a soldier? (7)
I believe the answer is:
I believe this is a double definition.
'force' is the first definition.
(I know that dragoon is a type of force)
'a soldier?' is the second definition.
(dragoon is a kind of soldier)
'to be' is the link.
(Other definitions for dragoon that I've seen before include "[CARIBINEER]?" , "Former heavily-armed cavalryman" , "Cavalry soldier" , "Shanghai" , "Cavalryman; coerce (into doing something)" .)