Borders are not walls, borders can be controlled while not keeping people in. Walls only have few doors and thus people get controlled
You are wrong. Obviously you can’t control 1500 miles of border without a wall when there is immigration pressure. Only a few entry points is exactly the aim. How many Americans are trying to escape to Mexico to be slaughter by the drug cartels?
The Israelis have shown effective border control with walls as part of the component. Trump has offered more than just a wall but even Paul Ryan recognizes a wall is a good start