One of the oldest military publications is The Art of War, by the Chinese philosopher Sun Tzu. Written in the 6th century BCE, the 13-chapter book is intended as military instruction, and not as military theory, but has had a huge influence on Asian military doctrine, and from the late 19th century, on European and United States military planning. It has even been used to formulate business tactics, and can even be applied in social and political areas.[where?]
Alongside this, World War II also inspired films as varied as The Dam Busters, 633 Squadron, Bridge on the River Kwai, The Longest Day, Catch-22, Saving Private Ryan, and The Sea Shall Not Have Them. The next major event, the Korean War inspired a long-running television series M*A*S*H. With the Vietnam War, the tide of balance turned, and its films, notably Apocalypse Now, Good Morning, Vietnam, Go Tell the Spartans, Born on the Fourth of July, and We Were Soldiers, have tended to contain critical messages.
The First World War was also responsible for a new kind of military depiction, through poetry. Hitherto, poetry had been used mostly to glorify or sanctify war. The Charge of the Light Brigade by Alfred, Lord Tennyson, with its galloping hoofbeat rhythm, is a prime late Victorian example of this, though Rudyard Kipling had written a scathing reply, The Last of the Light Brigade, criticising the poverty in which many Light Brigade veterans found themselves in old age. Instead, the new wave of poetry, from the war poets, was written from the point of view of the disenchanted trench soldier.
Soldiers and armies have been prominent in popular culture since the beginnings of recorded history. In addition to the countless images of military leaders in heroic poses from antiquity, they have been an enduring source of inspiration in war literature. Not all of this has been entirely complementary, and the military have been lampooned or ridiculed as often as they have been idolised. The classical Greek writer Aristophanes, devoted an entire comedy, Lysistrata, to a strike organised by military wives, where they withhold sex from their husbands to prevent them from going to war.
In Medieval Europe, tales of knighthood and chivalry, the officer class of the period captured the popular imagination. Writers and poets like Taliesin, Chrétien de Troyes and Thomas Malory wrote tales of derring-do, featuring Arthur, Guinevere, Lancelot and Galahad. Even in the 21st century, books and films about the Arthurian legend and the Holy Grail continue to appear.
During the war, significant advances were made in military communications through increased use of radio, military intelligence through use of the radar, and in military medicine through use of penicillin, while in the air, the guided missile, jet aircraft, and helicopters were seen for the first time. Perhaps the most infamous of all military technologies was the creation of the atomic bomb, although the exact effects of its radiation were unknown until the early 1950s. Far greater use of military vehicles had finally eliminated the cavalry from the military force structure.
International protocols restrict the use, or have even created international bans on weapons, notably weapons of mass destruction (WMD). International conventions define what constitutes a war crime, and provides for war crimes prosecution. Individual countries also have elaborate codes of military justice, an example being the United States' Uniform Code of Military Justice that can lead to court martial for military personnel found guilty of war crimes.
Limited Duty Officer: due to the highly technical nature of some officer billets, the Marine Corps, Navy and Coast Guard employ a system of promoting proven senior enlisted members to the ranks of commissioned officers. They fill a need that is similar to, but distinct from that filled by warrant officers (to the point where their accession is through the same school). While warrant officers remain technical experts, LDOs take on the role of a generalist, like that of officers commissioned through more traditional sources. LDOs are limited, not by their authority, but by the types of billets they are allowed to fill. However, in recent times they have come to be used more and more like their more-traditional counterparts.
Examinees also receive a score on what is called the Armed Forces Qualification Test (AFQT). AFQT scores are computed using the Standard Scores from four ASVAB subtests: Arithmetic Reasoning (AR), Mathematics Knowledge (MK), Paragraph Comprehension (PC), and Word Knowledge (WK). AFQT scores are reported as percentiles between 1-99. An AFQT percentile score indicates the percentage of examinees in a reference group that scored at or below that particular score. For current AFQT scores, the reference group is a sample of 18 to 23 year old youth who took the ASVAB as part of a national norming study conducted in 1997. Thus, an AFQT score of 90 indicates that the examinee scored as well as or better than 90% of the nationally-representative sample of 18 to 23 year old youth. An AFQT score of 50 indicates that the examinee scored as well as or better than 50% of the nationally-representative sample.