Is this named the Aztlan Project by any chance?
I don't know if this website was the one posted, but this was mentioned about a year ago in the context of integrated FTAA access. So you're right, there isn't any intention of securing the Southern border. With FTAA visas soon to be a reality, and integrated air/land corridors (complete with trucks from Mexico, Guatemala, Costa Rica, etc), it'll just be a free for all as everyone descends on us and never leave.