[Sivad]

With all this acquired political sophistication and shear numbers of
folks one might ask just why don’t these Mexicans return to their
home country and force reforms there? They can invade the most
powerful and successful democracy in the history of the world and
change the direction of this nation yet their own homeland remains
backwards and corrupt. What’s wrong with this picture?

[ScottinVA]

one might ask just why don’t these Mexicans return to their home country and force reforms there?

Because they came here not to better their lives, but to ultimately create an anschluess of the American Southwest and whichever else they can grab to Mexico.