Officer corps
An officer is a member of an armed force or uniformed service who holds a position of authority. Used without further detail, the term "officer" almost always refers to commissioned officers, the most senior portion of a force who derive authority from a commission, usually from a state, e.g., a "national" government. In this sense, officers are not "enlisted," but hold appointments from their government that typically remain in force indefinitely unless resigned.
In its broadest sense, the term "officer" also includes warrant officers and lower level enlisted leaders, the last category who are referred to as non-commissioned officers, to include petty officers and chief petty officers of navies and coast guards.
The proportion of officers varies greatly. Officers typically make up between an eighth and a fifth of modern armed forces personnel. In 2013, officers were the senior 17% of the British armed forces, and the senior 13.7% of the French armed forces. In 2012, officers made up about 18% of the German armed forces, and about 17.2% of the United States armed forces.
Historically, however, armed forces have generally had much lower proportions of officers. During the First World War, fewer than 5% of British soldiers were officers (partly because World War One junior officers suffered very high casualty rates). In the early twentieth century, the Spanish army had the highest proportion of officers of any European army, at 12.5%.
Within a nation's armed forces, armies (which are larger) tend to have a lower proportion of officers, but a higher total number of officers, while navies and air forces have higher proportions of officers. For example, 13.9% of British army personnel and 22.2% of the RAF personnel were officers in 2013, but the army had a larger total number of officers.
Having officers is one requirement for combatant status under the laws of war, though these officers need not have obtained an official commission or warrant. In such case, those persons holding offices of responsibility within the organization are deemed to be the officers, and the presence of these officers connotes a level of organization sufficient to designate a group as being combatant.
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