We are aware of the differences between Anglos and Latinos. In our oppinion as Latinos, that don't convert us in part of different civilisations but only of subcultures that evolved in different ways.
The tensions between Anglo and Latinos started very early, actually between the colonies that belonged to the Spanish and British empires. British have always demonized Spaniards considering them inferior, cruel and all kind of bad attributes. The actitudes of Americans towards Latinos seems to be just a continuation of that.
After Independence, there was a short period when it was possible to unify North America and Hispanic America in a single continental society. Hispanics tried to get into agreements with Americans, but they didn't care. However, in 1840s, the expansion to the West that consisted mainly in taking lands from Indians become a campain to take lands from Mexicans; who were considered inferiors as Indians. Since then and up to recently the U.S. considered Latin America was its property and it could do there whatever they want. Latin America was invaded or intervened more than 100 times from 1840 to the end of the 20th century.
As a revenge, perhaps, Latin America started to send its surplus people to the U.S. Perhaps following the old saying "If you can't defeat them, join them".
The last chapter of this long friendship was the construction of the wall between the U.S. and Mexico, promoted by Bush, and that ended in a massive strike by Hispanics in the U.S.
The Hispanic revenge happened soon later, when Hispanics voted in mass for Obama and against the Republicans.
Today close to the 20% of the U.S. population is Hispanic, so I expect the saying of this group will have more weight in the future.