He is highlighting the need for basic and COMPREHENSIVE reforms of our voting system.

Universal ID for all citizens and registered legal aliens is needed. That would end a lot of issues connected with voter fraud, and also illegal use of US social services, which would in turn ease a lot of immigration-based issues.

Right now, they want to build a wall because it is too easy to get over here, get established as a resident and build a life. If we make that more difficult through a mandatory citizen/resident alien ID system, then we have removed a lot of that incentive.

And it would be a fuck of a lot cheaper than buying all that land and building, maintaining and patrolling a thousand-plus of miles of wall.