In the years immediately after World War II, several scholars argued, — Unit cohesion

"Siebold (2007) describes the “standard model” of cohesion as involving peer (horizontal), leader (vertical), organizational, and institutional bonding, each having an affective component and an instrumental component. He focuses on the role of trust and teamwork, as well as self-interest, in building cohesion: The essence of strong primary group cohesion, which I believe to be generally agreed on, is trust among group members (e.g., to watch each other’s back) together with the capacity for teamwork (e.g., pulling together to get the task or job done). [p. 288] . . . Combat group members try to develop strong bonding as a collective good, at least in part, because it is in their own self-interest for survival to do so. [p. 289] . . . While it is true that a few researchers have focused on intimate personal bonds and informal rituals, I submit that the majority of researchers . . . have used some form or part of the standard model in their approach, especially during the past twenty years, which does not dwell on intimate relations or masculine rituals but rather emphasizes interpersonal trust and teamwork built through many experiences including arduous training and drills. [p. 291] . . . [M]ere friendship or comradeship is not the essence of cohesion. [p. 292]"

"Several recent studies have examined the effects of race, ethnicity, and gender on military cohesion. Siebold and Lindsay (2000) noted that “a central tenet of current personnel policy is that the Army can recruit 17- to 21-year-old men [sic] . . . from different demographic backgrounds, train them, and assign them to groups with leaders, who also have different demographic backgrounds, to form cohesive, motivated, and competent combat units.” They report on an Army Research Institute study of 60 light infantry platoons (955 soldiers) at the U.S. Army Joint Readiness Training Center and NTC. Soldiers completed a detailed questionnaire assessing squad cohesion and related attitudes. The average self-reported cohesion rating was around 3.4 on a 5-point scale (5=high cohesion), with no differences in self-reported cohesion ratings for white, black, Hispanic, and Asian soldiers. The researchers noted that “[t]his pattern of little differentiation based on racial or ethnic (demographic) group membership is typical. The unit’s internal conditions, including leadership quality, appear to be the dominant influences on soldier cohesion and motivation.”"

"The post-Vietnam–era military scholars began articulating a view of cohesion that emphasizes the importance of task cohesion. For example, an influential definition of military cohesion was offered by Wm. Darryl Henderson in his 1985 book, Cohesion: The Human Element in Combat. His vision is clearly more in accord with task cohesion than social cohesion: Cohesion exists in a unit when the day-to-day goals of the individual soldier, of the small group with which he identifies, and of unit leaders, are congruent— with each giving his primary loyalty to the group so that it trains and fights as a unit with all members willing to risk death and achieve a common objective. (Henderson, 1985, p. 4)"

"In the theater of operations . . . the presence of the enemy, and his capacity to injure and kill, give the dominant emotional tone to the combat outfit. . . . The impersonal threat of injury from the enemy, affecting all alike, produces a high degree of cohesion so that personal attachments throughout the unit become intensified. Friendships are easily made by those who might never have been compatible at home, and are cemented under fire. Out of the mutually shared hardships and dangers are born an altruism and generosity that transcend ordinary individual selfish interests. So sweeping is this trend that the usual prejudices and divergences of background and outlook, which produce social distinction and dissension in civil life, have little meaning to the group in combat. Religious, racial, class, schooling or sectional differences lose their power to divide the men. What effect they have is rather to lend spice to a relationship which is now based principally on the need for mutual aid in the presence of enemy action. Such powerful forces as antisemitism, anticatholicism or differences between Northerners and Southerners are not likely to disturb interpersonal relationships in a combat crew. . . . Their association is not limited to working hours but includes their social activities. . . . The most vital relationship is not the purely social. It is the feeling that the men have for each other as members of combat teams and toward the leaders of those teams, that constitutes the essence of their relationship."

"When I was bleeding to death in my Black Hawk helicopter after I was shot down, I didnt care if the American troops risking their lives to help save me were gay, straight, transgender, black, white or brown."

"Elsewhere, Moskos, as cited in Marlowe (1979), referred to this social compact as “instrumental and self-serving.” But a less cynical framing is provided by the growing literature on the importance of “swift trust” in high-stakes settings (Kramer, 1999; Majchrzak, Jarvenpaa, and Hollingshead, 2007; Meyerson, Weick, and Kramer, 1996). Trust that is based on strong interpersonal bonds can take a long time to develop (McAllister, 1995; Webber, 2008). But Meyerson, Weick, and Kramer (1996) note that professional teams often “have a finite life span, form around a shared and relatively clear goal or purpose, and their success depends on a tight and coordinated coupling of activity.” Majchrzak, Jarvenpaa, and Hollingshead (2007) examined various case studies in the development of swift trust among complete strangers in response to natural disasters. Kramer (1999) reviewed evidence for several different ways in which this kind of swift trust develops, including category-based trust (based on knowledge of the other person’s membership in trusted groups), role-based trust (e.g., using high rank as a measure of one’s past experience and performance), and rule-based trust (based on “shared understandings regarding the system of rules regarding appropriate behavior,” p. 579). These mechanisms may work through either task cohesion or social cohesion, depending on the setting. Thus, when people rely on someone’s professional certification (e.g., as a surgeon, engineer, or musician), there may be a rapidly established task cohesion. If, however, one were to rely on credentials from a fraternal organization, the swift trust might rapidly create social cohesion. Similarly, rule-based trust might promote task cohesion in professional settings but social cohesion in social organizations.Of course, these routes are not mutually exclusive; professional conferences organize social outings, and fraternal groups organize charitable works."