have forgotten all about it and it is necessary. somehow the entire argument has been reduced to a physical wall we have once tried with physical and electronic surveillance and fencing through sbi-net, the secure border initiative. and it did not work. like, i don't know why we're not having that conversation either. it's very important. i'm going to continue to repeat it, because i hope somebody will hear it. >> and remember also, there's a question about what will constitute the wall you're talking about and kaitlan collins asked the president about whether it's going to be concrete, steel slats or whatever he said. take a listen. >> you ran your campaign promising supporters mexico is going to pay for the wall. >> here we go again. >> and the wall would be made of concrete. you just said earlier the wall would be made of steel. >> i said i'm going to build a wall. i never said concrete. i know you're not into the construction business. you don't understand something. we now have a great steel business that's rebuilt in the united states. steel is stronger than concrete.