From Wendell Berry (an amazing writer/thinker who was way before his time on sustainable agriculture and all related things):
Mexicans cross the border because our way of life is extravagant; because our way of life is extravagant, we have no place for them - or won't have for very long. A generous immigration policy would be contradicted by our fundamentally ungenerous way of life.
- "A Few Words in Favor of Edward Abbey," in the book What Are People For?
Just after I read this, I happened to hear the same line of thinking in this YouTube video. (I found the video after searching for something by Jonathan Wilson-Hartgrove, who wrote a great book about working to erase the division between black and white churches that I just read.) The woman at the end of the panel describes America as hoarding all the resources in the world then drawing a line around them and not letting other people come in.
I realize that immigration is a touchy subject, but how do we reconcile what we are as America with how we're called to treat the poor, the aliens, the oppressed?