There's nothing quite like starting out with a false premise.
Could you give me an estimate of how many border patrol officers/soldiers it would take to seal off the Southern border. Then how many naval patrol boats it would take to seal off the Gulf of Mexico, Atlantic Ocean and the Pacific Ocean? Then how many to seal off the Northern border?
Can you give me an estimate of the cost? Would we have to withdraw troops from Iraq or institute a draft?
Then who would replace the immigrant laborers? Will you repair roofs and clean septic systems, and pick melons in the hot Texas sun? Do you really think that the unemployed American office workers, managers, and foremen of the industries that have to relocate to Mexico to get employees will be willing to mow lawns for a living?