It's worth looking at how that environment is produced too. There's a need for cheap labor in agriculture, laundry, hospitality and textile industries that dovetails well with the US's history of anti-mexican racism (grounded in the need to dehumanizing indigenous people to steal their land as well as the US-Mexico war).

By controlling people's movement through the border regime, we can make them willing to take sub-minimum wage jobs, while also keeping Mexico poor through lopsided trade agreements like NAFTA and low level insurgency achieved by escalating the drug war and flooding the country with weapons.

In this context of US oppression of Mexicans, it becomes necessary to dehumanize them to justify the violence. This is where fox news comes in. Hell, even CNN plays a role by creating categories of migrants some good and some bad, and playing them against each other while justifying border control (think about the rhetoric about dreamers vs drug smugglers).

To change this environment, we either need to undercut this propaganda by organizing white and brown workers together, or either take back control of media from big business or make our own media with similar reach.