I think it's a big backfire.
Pssst....time for American companies to pull out of Mexico.
Double Pssssst!!
Time totally tostop all normal surface traffic from Mexico altogether.
I'm sure there will be screams, but a Sovereign Nation's physical and health security of its citizens trumps all other considerations, even economic ones.
Humanitarian considerations? The biggest manufactured red herring of all!
Whether it is a big backfire depends on what you believe his ultimate goal is. If you believe it is to get the republicans to move on providing amnesty for illegals, it is a big backfire fail. But if his ultimate goal is to open the borders and allow as many illegal aliens, drugs, cartel gang members, red Chinese and jihadis into this country as possible, he has been tremendously successful.
Why do we have to go through TSA searches when all the illegals and arabs have to do is get on the plane with a piece of paper or walk across our southern border.