Final answer:
The main argument of the coercive theory of early state formation is that states emerged due to the need for centralized political power to effectively use coercive force and maintain control over a defined geographic area.
Step-by-step explanation:
The main argument of the coercive theory of early state formation, developed by Robert Carneiro in the 1970s, is that states emerged due to the need for centralized political power to effectively use coercive force and maintain control over a defined geographic area. Carneiro argued that as population density increased, competition for resources and territories intensified, leading to the rise of states as a means of protecting and controlling people.