We don't have to expell them. Take away the incentives to come here (jobs, free medical care, any social services, no possibility of EVER getting a green card later if caught illegall in the US) and many will tale themselves home, just like they brought themselves here. Anyone who says it is not possible either doesn't want it done, or isn't very imaginative.
Oh, and having lived most of my life in the southwest, I can say that Mexicans are like everyone else. You have good and you have bad. I find it interesting that almost everyone who posts on the subject says they are the best people there are. That simply is not true. They are like everyone else, some good, some bad.
susie
Your last sentence sums up the defeatist, pro-illegal crowd perfectly. I would say that most fall in the first category.