The bottom line is that according to the Constitution and Federal law, setting immigration policy is at the president's whim.
Rest assured, if THEIR President was sitting in the oval office and the Right was able to interfere with him (or her) to the extent the Left has done, they'd be in the streets burning down America coast to coast.
I would say the Right would never be allowed to interfere with their President. The media and many parts of the government would help ensure it and they know it.
We are already off the precipice.
America as a nation of law and order and justice is already gone as evidenced by the Patriot Act, Presidents with "Pen and phones", Federal Bureaus that cover for corrupt candidates, an IRS used as a political weapon, judges preventing the President from securing the naton.....
We're already gone.
The question is how fast it will deteriorate from this point