It is a third world hell hole for the most part and to annex it as you suggest would be the gretest drain on this economy in history. They would ALL be citizes then, and legal, and they would all immediately qualify for welfare.
We would lower our own standard of living by half (or more) trying to fund it, and we would ensure the democratic party was in power for generations.
Sorry, the medicine you propose is much worse than the current ill.
We can enforce our laws. If we immediately became firm with the firms hiring the illegals, and began wholesale deporting hundreds of thousands, the rest would go home on their own...at leat most of them. You would be left with the criminal element who we need to route out anyway.
In addition, if the program said in essence...if you are here illeally and volunteer to report at a border station or INS office for deportation, you will be sent home, but we will accept you immigration application from Mexico in line with everyone else when you apply. However, if you do not, and we catch you, then we will incarcerate you for a time and you will be forcibly depoted thereafter with DNA identification retained and you will NEVER be eligible for immiration to the US.
We will take a hit to the n economy...but we have taken hits before. That is better than letting the invasion and illegality continue.
Those are my thoughts.
I think you're right on point with your comments. We don't want Mexico. Mexico should right it's own ship of state. Besides, I wouldn't want to deny the Mexican citizens their own nation any more than I would want them to deny us ours.