Gang presence in the United States military

Gang presence in the United States military is a phenomenon in which members of American street gangs such as the Crips, Latin Kings, Aryan Brotherhood and many others either join the United States Armed Forces, or are recruited to join the gangs while already in the military.

Extent
In 2008, FBI gang investigator Jennifer Simon stated that 1-2% of the U.S. military belongs to gangs, which is 50-100 times the rate in the general population. According to the Federal Bureau of Investigation's 2011 National Gang Threat Assessment, the NGIC has identified members of more than 53 gangs who have served in the United States military, including Bloods, Crips, Latin Kings, MS-13, Sureños, the Aryan Brotherhood, Barrio Azteca, Bandidos, Hells Angels, and Gangster Disciples.

U.S. gangs have sometimes encouraged their members to join the military in order to learn urban warfare techniques, which they could then teach other gang members when they returned from service. A January 2007 article in the Chicago Sun-Times reported that gang members in the military are also involved in the theft and sale of military weapons, ammunition, and equipment, including body armor.

Reports
The FBI’s 2007 report on gang membership in the military stated that the military's recruit screening process is ineffective, and allows gang members/extremists to enter the military. The report listed at least eight instances in the previous three years in which gang members had obtained military weapons for their own use.

"Gang Activity in the U.S. Armed Forces Increasing", dated January 12, 2007, stated that street gangs including the Bloods, Crips, Black Disciples, Gangster Disciples, Hells Angels, Latin Kings, The 18th Street Gang, Mara Salvatrucha (MS-13), Mexican Mafia, Nortenos, Surenos, and Vice Lords have been documented on military installations both domestic and international, although recruiting gang members violates military regulations.

Gang graffiti in Iraq
U.S. gang-related graffiti has shown up in Iraq since the beginning of the Iraq war in 2003. Among the largest American street gangs represented in Iraq are the Gangster Disciples, Crips, Bloods, 18th Street, Nortenos, Black Disciples, Surenos, Latin Kings, TAP Boyz, Vice Lords, and Black P. Stones, which originated in some of Chicago's most violent and impoverished neighborhoods. There are also reports of Black Power, African Nations, Aryan Nations, Aryan Brotherhood and Ku Klux Klan gang graffiti in Iraq.