So I've been checking up time to time on the progress on the construction of the borderwall https://www.cbp.gov/border-security/along-us-borders/border-wall-system Overall despite the Set backs and hurdles it looks like Trump has kept his promise for the most part on getting the wall built, a good bulk of it is now up(415 miles at this time of writing) although it looks like it isn't all going to be finished by the time he leaves office. So I'm just curious how much of the wall actually need to be put up? As I understand not all the US-Mexico border is porous, a good...