The activities of the Mexican cartels are mostly ( I say 'mostly') limited to supplying narcotics. They are the importers, middle men are La Eme, Aryan Brotherhood, Hells Angels, MS13,...who in turn sell it to smaller groups.
Dixie Mafia, Black Guerilla Family, Gangster Disciples,...mostly work with Colombians.
Neither the Mexicans nor the Colombians are almighty, eventhough Mexican cartels control the importation of narcotics in the Southwest and a good chunk of the deep South, while Colombians mostly control the importation in the Southeast.

The power of the 'homegrown' groups ( not including the more recent Albanian, Russian, Dominican, Cuban, Asian,...arrivals) can be divided as such : Italian-American OC is the most powerful in the northeast and small parts of the midwest, while everything west and south is divided between Chicanos, African-Americans and White Southerners. This concerning 'homegrown' OC.