War is an organized, armed, and, often, a prolonged conflict that is carried on between states, nations, or other parties typified by extreme aggression, social disruption, and usually high mortality.[1][2] War should be understood as an actual, intentional and widespread armed conflict between political communities, and therefore is defined as a form of political violence.[1][3] The set of techniques used by a group to carry out war is known as warfare. An absence of war (and other violence) is usually called peace. In 2003, Nobel Laureate Richard E. Smalley identified war as the sixth (of ten) biggest problem facing the society of mankind for the next fifty years.[4] In the 1832 treatise On War, Prussian military general and theoretician Carl von Clausewitz defined war as follows: "War is thus an act of force to compel our enemy to do our will."[5] While some scholars see warfare as an inescapable and integral aspect of human culture, others argue that it is only inevitable under certain socio-cultural or ecological circumstances. Some scholars argue that the practice of war is not linked to any single type of political organization or society. Rather, as discussed by John Keegan in his History of Warfare, war is a universal phenomenon whose form and scope is defined by the society that wages it.[6] Another argument suggests that since there are human societies in which warfare does not exist, humans may not be naturally disposed for warfare, which emerges under particular circumstances.[7] The ever changing technologies and potentials of war extend along a historical continuum. At the one end lies the endemic warfare of the Paleolithic[citation needed] with its stones and clubs, and the naturally limited loss of life associated with the use of such weapons. Found at the other end of this continuum is nuclear warfare, along with the recently developed possible outcome of its use, namely the potential risk of the complete extinction of the human species. The English word war derives from the late Old English (c.1050) words wyrre and werre; the Old North French werre; the Frankish werra; and the Proto-Germanic werso. The denotation of war derives from the Old Saxon werran, Old High German werran, and the German verwirren: “to confuse”, “to perplex”, and “to bring into confusion”.[8] Another posited derivation is from the Ancient Greek barbaros, the Old Persian varhara, and the Sanskrit varvar and barbara. In German, the equivalent is Krieg; the equivalent Spanish, Portuguese, and Italian words for "war" is guerra, derived from the Germanic werra (“fight”, “tumult”).[9] Etymologic legend has it that the Romanic peoples adopted a foreign, Germanic word for "war", to avoid using the Latin bellum, because, when sounded, it tended to merge with the sound of the word bello ("beautiful") Before the dawn of civilization, war likely consisted of small-scale raiding. One half of the people found in a Nubian cemetery dating to as early as 12,000 years ago had died of violence.[10] Since the rise of the state some 5,000 years ago,[11] military activity has occurred over much of the globe. The advent of gunpowder and the acceleration of technological advances led to modern warfare. According to Conway W. Henderson, "One source claims 14,500 wars have taken place between 3500 BC and the late 20th century, costing 3.5 billion lives, leaving only 300 years of peace (Beer 1981: 20)."[12] In War Before Civilization, Lawrence H. Keeley, a professor at the University of Illinois, says that approximately 90–95% of known societies throughout history engaged in at least occasional warfare,[13] and many fought constantly.[14] Japanese samurai attacking a Mongol ship, 13th century Keeley explained several styles of primitive combat such as, small raids, large raids, and massacres. All of these forms of warfare were perpetrated by primitive societies. The use of the massacre by pre-state societies can be exhibited by the Dogrib tribes of the subarctic in North America. The Dogrib tribe eventually destroyed the Yellowknife tribe by killing 4 men, 13 women, and 17 children which accounted for 20 percent of the population.[10] This was a devastating blow from which the Yellowknife tribe never recovered. Keeley further explains how small raids are not organized due to the lack of leadership and any formal training. This causes raids to be short and quick with relatively low numerical casualties but may significantly damage a percentage of a population. The deficit of resources also can account for a lack of fortifications and defensive structures in primitive prestate societies. The protection provided by a defensive could not justify the valuable resources used and labor implemented to build it.[10] William Rubinstein wrote that "Pre-literate societies, even those organised in a relatively advanced way, were renowned for their studied cruelty ... 'archaeology yields evidence of prehistoric massacres more severe than any recounted in ethnography [ie, after the coming of the Europeans]'. At Crow Creek, South Dakota, as noted, archaeologists found a mass grave of 'more than 500 men, women, and children who had been slaughtered, scalped, and mutilated during an attack on their village a century and a half before Columbus's arrival (ca. AD 1325)' ".[15] In Western Europe, since the late 18th century, more than 150 conflicts and about 600 battles have taken place.[16] According to the U.S. Bureau of the Census (1894), the Indian Wars of the 19th century cost the lives of about 19,000 whites and 30,000 Indians.[17] The Human Security Report 2005 documented a significant decline in the number and severity of armed conflicts since the end of the Cold War in the early 1990s. However, the evidence examined in the 2008 edition of the Center for International Development and Conflict Management's "Peace and Conflict" study indicated that the overall decline in conflicts had stalled.[18] Recent rapid increases in the technologies of war, and therefore in its destructiveness (see Mutual assured destruction), have caused widespread public concern, and have in all probability forestalled, and may altogether prevent the outbreak of a nuclear World War III. At the end of each of the last two World Wars, concerted and popular efforts were made to come to a greater understanding of the underlying dynamics of war and to thereby hopefully reduce or even eliminate it all together. These efforts materialized in the forms of the League of Nations, and its successor, the United Nations.