The left will never admit a wall would work, but as we all know, the left are not very good at predictions.
I recently created a topic on what Hungary has done. They put up border fences and cut their immigration down by almost 100%, and the left still wouldn't admit borders are the solution.
Even after we build the wall and it shows positive results, the left will make claim the wall had nothing to do with it. it's just like they are not giving credit to Trump for the economy. They are still saying it's DumBama's doing.