Southern Mexico is furtile ground.
Wherever you find ignorance you will find Islam.
It's not just ignorance, it's also about hatred. Islam gives non-Whites legitimacy for those among them who hate Whites. The Nation of Islam can now talk in terms of "killing the Infidel" in terms of being open racists and talking about "killing Whitey". Muslims conduct extensive Da'wa throughout the world, especially the third world but also the West, and they are builing a strong jihadist fifth column. Notice the recent successful jihadist takeover in Somalia and the institution of shari'a there.