“....could lead to a recession and spur more migration north.”
There will be a BIG WALL and vastly increased border patrols. Mexicans “migrate north” all the please but they will be STOPPED by the wall.
Besides if they were able to get over the border to the US, provided law was enforced, they couldn’t get a job, get a license to drive, send money back to Mexico, send there kids to school here or get any kind of g’mint assistance.