One thing that is never mentioned on the issue of immigrants is how it all began in the 19th century. Before Texas became US territory the Mexico owned the land which was forcibly taken from them.
The situation started when Mexico allowed Americans to immigrate into what was a semi-autonomous province. Every thing was fine until the Mexican government want to abolish slavery throughout it's nation. They also wanted to impose a modest tax on the residents in Texas. Mexico had the sovereign right to do both.
However, Texans did not take too well to that because they saw themselves entitled to own slaves and to not contribute even a modest amount to the nation that gladly brought them in.
Now the Mexicans are coming back to where many of their ancestors used to live; irony, irony. There is a place for Mexicans here in the US but I acknowledge that there would be way too many of them with an open border.
As for legal immigration I would ban it because there aren't enough jobs for those who already live here. We receive 1 million legal immigrants a year which adds up to 10 million in one decade. That's a lot of jobs. Remember that the main reason people oppose Mexicans streaming over the border has to do with their taking jobs away from us. Therefore, it doesn't matter that legal immigrants have this aura of acceptability; there just are not enough jobs for everyone.