<P> A military is a force authorized to use lethal or deadly force and weapons to support the interests of the state and some or all of its citizens . It typically consists of an Army , Navy , Air Force , and in certain countries the Marines and Coast Guard . The task of the military is usually defined as defence of the state , and its citizens , and the prosecution of war against another state . The military may also have additional sanctioned and non-sanctioned functions within a society , including , the promotion of a political agenda , protecting corporate economic interests , internal population control , construction , emergency services , social ceremonies , and guarding important areas . The military may also function as a discrete subculture within a larger civil society , through the development of separate infrastructures , which may include housing , schools , utilities , logistics , health and medical , law , food production , finance and banking . In broad usage , the terms `` armed forces '' and `` military '' are often treated as synonymous , although in technical usage a distinction is sometimes made in which a country 's armed forces may include both its military and other paramilitary forces . Armed force is the use of armed forces to achieve political objectives . There are various forms of irregular military forces , not belonging to a recognized state ; though they share many attributes with regular military forces , they are less often referred to as simply `` military '' . </P>
what is the main purpose of the military
to support the interests of the state and some or all of its citizens