The Mexican mafia also works methodically to take over neighborhoods. The bosses subsidize purchase of houses and move in trusted Mexican families. Often they don't speak English at all. They house multiple families in single-family homes, park their cars in front of their neighbors' driveways and other annoying passive-aggressive moves… once there are several families installed in a neighborhood, they begin the overt hate speech, vandalism and petty crimes against their non-Hispanic neighbors. Rinse and repeat until the whole neighborhood is Mexican. At that point, the Mexican mafia has a "safe space" within which to openly operate their drug-dealing and human-trafficking businesses.
It's methodical, a tried and true formula. I've seen a few neighborhoods succumb; enough examples that I recognize the pattern.