I have noticed a fairly massive disconnect between the outrage that this bill has received and what it actually attempts to do; and the main reason for this is fear-mongering by individuals who refuse to attempt to understand the bill.
If you travel (pretty much) anywhere in the world, or go to live in another country, any dealings with the police (or any government agency) will require you to verify that you’re in the country legally by having you provide certain paperwork; and if you’re not in the country legally you will probably be deported or imprisoned. There are several reasons for this including the general safety and security of their citizens; but besides those, it is simply not fair to the countless qualified potential immigrants you turn down to allow a queue-jumper to remain in your country.
Mexico really does not want the border patrolled because it acts as a pressure valve by allowing millions of its citizens with very low standards of living an (virtually) no prospects to flee the country; and this allows the country to ignore the systemic problems which keep the standard of living of so many citizens so low, with such few prospects.
